Pain and Pain control in Dogs

by
,

Pain control


My current goals are to recognize conditions that might be painful and to treat for the pain whenever it seems best to do that. A guideline that I use is to imagine if the condition would be painful if it was happening to me. I have had abdominal surgery so I can tell you that there is pain during the recovery period. So we dispense pain control medications for our surgery patients. I have talked to people who have had pancreatitis and they tell me the pain is severe so I try very hard to control pain in patients with this condition. If you think that a condition might be painful for your pet, pain relief is a good idea.

There are two broad categories of pain that are useful to think about because treatment options vary pretty significantly between them. Acute pain is suddenly occurring pain in response to an injury that disappears as the injury heals. Chronic pain is pain that persists after an injury has healed or that persists due to a damaging process that also persists, such as arthritis.

One of the interesting things about pain is that there seems to be a mechanism in the body for "remembering" pain -- events that were painful in the past may cause pain more easily the next time. In addition, some pain appears to become imprinted in the neurologic pathways and to persist even after an injury is healed. This is the one of the reasons that "phantom pain" associated with an amputated limb is believed to occur. Working towards decreasing these remembered and imprinted pain sensations has opened up a whole new area of research in pain relief.

Another interesting thing about pain is that it is a threshold event. I have always had a hard time explaining this concept to people. One way of looking at this is to think about how much more a second painful stimulus hurts when someone is standing on your foot. The pain from being stepped on caused enough discomfort to get near or possibly over the pain threshold and the second event gets a head start on causing pain because the nervous system is already at the pain threshold.

Another way of thinking about it is like a seesaw. You can put a rock on the high end of seesaw and it might not cause it to go down. If you add a second rock that might not move it, either. But eventually you will reach the point where the weight on the upper end suddenly causes the high end of the seesaw to fall. This is how pain threshold works. You really don't feel pain even though something has the potential to cause it until there is enough "weight" to tip over the pain threshold -- then you feel it suddenly.

The pain threshold has been demonstrated in good scientific studies to vary as much as fivefold between individuals who have a "low" pain threshold and those with a "high" pain threshold. This means that it takes five times as much pain stimulus to cause the people or pets at the high end of the spectrum to feel pain. There is nothing psychological about the difference to the best of researcher's ability to tell. Some animals and some people just have more sensitivity to pain. We see this routinely in our practice with the simple act of vaccinating pets. Some dogs and cats act as if the injection is severely painful every time and others don't even look back to see what we did. Knowing that there really is a big difference in how pain is perceived has helped me to give the pets who seem overly sensitive a break --- I just assume now that they really do feel pain more easily and that their complaints are justified.

The best way to deal with acute pain is to give pain relievers before it occurs. When this is done it can be demonstrated easily that lower doses of pain relief can control the pain and that the duration of need for pain relief is often shorter. This works well for situations in which pain can be anticipated, such as surgery, but it doesn't help much with pain that is due to an unexpected injury. When pain relievers must be given after an injury has occurred it sometimes takes much higher doses to tamp down the pain and get it under control. It is good to keep this in mind, because many people make the mistake of using low doses of pain reliever initially, hoping they will work. It is probably better to start with high doses and then to cut the dosage if it becomes apparent that lower dosages will work.

There are a number of available options for acute pain relief in dogs. There are fewer options in cats but there has been some progress in obtaining pain relief for this species over the last few years.

I am going to try to give the basic facts for a number of pain relief medications in the remainder of this month's VetInfo Digest. I am going to stick to pain relief medications that can be given at home. There are a number of additional pain relief medications that can be used in hospital situations in which intravenous use or injections of pain relief medications is possible. This is a field that is also rapidly expanding and your vet should be able to provide good pain relief for a pet in the hospital situation.

Remember when reviewing the following listing of medications that no veterinarian is likely to be familiar with all of them and some may be impractical for most pet owners. It is my intention to show that there are a variety of possibilities for achieving pain relief and often several possible medications in each pain relief category. It is usually possible to find some way to control pain with medications in most patients but there are some situations in which pain control is extremely difficult to achieve without surgery (such as amputation of a leg for relief of pain from bone cancer) or advanced pain control measures (such as alcohol blocks of individual nerves, permanently disabling them).

 

Nonsteroidal anti-inflammatories (NSAIDs)


The nonsteroidal anti-inflammatory medications are the mainstay of pain relief in dogs. Unfortunately, cats do not tolerate this group of medications very well, with a few exceptions. Many clients view NSAID medications as safe, based on the fact that many of them are over-the-counter medications for human use. Despite this general feeling of safety it should be noted that aspirin alone is suspected of causing approximately 16,000 deaths per year in the United States due primarily to gastric or intestinal ulcers. This group of medications is safer in many respects than other classes of pain relief medication but they are not entirely risk free. NSAIDs are frequently used for both acute and chronic pain.

Older NSAIDs such as aspirin, ibuprofen, ketoprofen and naproxen are more likely to cause ulcers than newer medications, referred to as "Cox2 inhibitors". On the other hand, when the Cox-2 inhibitors cause problems they can be more severe. So there is kind of a tradeoff between fewer side effects and more severe side effects. There is some controversy over whether the newer drugs actually provide more pain relief than the older ones. I definitely fall in the camp who believes that the Cox-2 inhibitors are more effective pain relievers for chronic pain.

It is very important to stop administering any NSAID and to call your vet if your pet stops eating or even has a significant decrease in appetite while the medication is being used. It is also quite important to let your vet know if you are using an over the counter pain relief medication at the time of yearly visits and especially when your vet is prescribing a medication for another purpose. Medications do interact and your vet must know that a medication is being given in order to take interactions into account.

There are a number of NSAIDS available for use in dogs and cats (and some common ones that shouldn't be used):

Aspirin: The recommended dosage for aspirin in dogs is 10mg/lb of body weight every 12 hours. The recommended dosage of aspirin for cats is controversial but a good starting point is 10mg/lb of body weight every 48 to 72 hours. Aspirin has a very long half life in cats and it is very easy to overdose a cat if aspirin is given on a daily basis. It is best to use aspirin under the supervision of your vet when using it in cats.

Ibuprofen (Motrin tm, Advil tm, others): it is generally agreed that the risk of gastrointestinal ulceration is high enough with this medication that its use is not advisable in either dogs or cats. In at least one study 100% of dogs given ibuprofen for a week developed gastrointestinal ulceration detectable by endoscopy. Despite this I have had a number of clients tell me they were using ibuprofen without visible ill effect, so if you happen to be doing this don't panic, but do switch to an alternative medication.

Ketoprofen ( Orudis KT tm): The recommended dosage of ketoprofen for dogs is 1mg/kg every 24 hours. Some texts advise using this for no more than 5 days. If a longer dosing period is necessary using 0.5mg/kg once a day may be safer and still effective. Ketoprofen may be used with great caution in cats at the same dosage but it is hard to do this practically, since the tablets are 10mg in size, which is the dosage for a 22 lb. cat or dog.

Naproxen (Aleve tm): The published dosage for dogs is 1.1 to 2.2mg/kg given once a day or every other day. Naproxen is not recommended for use in cats. Despite the existence of a published dosage we have seen ulcers in three dogs associated with the use of naproxen by pet owners. While none of them seemed very clear about the dose they were using this has caused us enough concern that we feel that naproxen should not be used in dogs or cats.

Etodolac ( Lodine Rx, Etogesic Rx): is approved for use in dogs. It provides good pain relief for long term conditions but has a tendency to cause a decrease in tear production which can be a really severe side effect. For this reason, it is very important to watch for any signs of eye pain or discomfort when using etodolac long term and to discontinue use if these problems develop. The recommended dosage in dogs is 10 to 15mg/kg once a day. Etodolac should not be used in cats.

Tolfenamic acid: is approved for use as a pain reliever in Europe and Canada but not in the U.S. It is dosed on an unusual schedule requiring three days of dosing followed by four days without medication, which is very important to follow. It is used in both dogs and cats. The recommended dosage is 4mg/kg or less once daily for 3 days, repeating the dosage after a 4 day rest if necessary to use chronically.

Piroxicam (Feldene Rx): is a potent NSAID that has some unusual benefits for certain conditions. It can be used solely for its pain relieving capability but since it is more likely than most NSAIDs to cause gastrointestinal ulceration its use is usually reserved for conditions in which it's other benefits are more meaningful. The recommended dosage is 0.3mg/kg every 48 hours (can be used every 24 hours for the first two doses). In cats it is sometimes used at 72 hour intervals rather than 48 hour intervals. Piroxicam has the ability to dramatically shrink some forms of cancer, especially transitional cell carcinomas of the urinary bladder. It also seems to help with severe bladder inflammation associated with chronic cystitis. There is some evidence that piroxicam is also effective for shrinking nasal tumors and reducing discomfort associated with this type of tumor. It may be best to administer misoprostol, a gastrointestinal protectant, when using piroxicam.

Meloxicam (Metacam Rx): The recommended dosage in dogs is 0.2mg/kg on the first day, then 0.1mg/kg every 24 hours. There is a measured dosing syringe for the liquid form of this medication. Meloxicam is generally regarded to have more of a Cox-2 spectrum in its action. It is available as a honey flavored liquid or in tablets. Meloxicam is only approved for use in dogs in the United States but it has been studied for use in cats and seems to be reasonably safe. The recommended dosage for cats is 0.1mg/kg once a day for 5 days, then 1 drop from the standard dispensing bottle for chronic use. Our experience has been that meloxicam works well at the higher initial dosage but doesn't seem to work nearly as well for chronic pain if the lower long term dosing schedule is used. This may or may not be a typical experience.

Deracoxib (Deramaxx Rx): The recommended dosage for dogs for acute pain is 3 to 4mg/kg/day. For chronic pain the dosage is 1 to 2mg/kg/day. This is a Cox-2 inhibitor. Based on our clinical experience this is the most potent of the NSAID pain relievers, on the average. There are individual variations among patients, though. There have been some reports of sudden severe gastrointestinal bleeding associated with the use of deracoxib, which is similar to the experience with Cox-2 inhibitors in people. This medication is not recommended for use in cats.

Carprofen ( Rimadyl Rx): The recommended dosage for dogs is 1mg/lb every 12 hours or 2mg/lb every 24 hours. In chronic pain situations it is often possible to use 1mg/lb per day successfully, although this does vary from dog to dog. This is a predominantly Cox-2 inhibitor. There are confirmed cases of liver failure associated with the use of carprofen (considered to be a rare complication), so it is best to check blood work for liver damage prior to use and to recheck lab work after 2 to 4 weeks of use. Carprofen is not approved for use in cats but it is sometimes used on a one time basis for pain relief associated with surgeries such as spay or neuter procedures.

Tepoxalin (Zubrin Rx): The recommended dosage of tepoxalin in dogs is 10mg/kg once a day. This medication suppresses both Cox-1 and Cox-2 systems. Tepoxalin is not approved for use in cats and I have not seen a published dosage to use in this species. Zubrin is the most recent of the primarily Cox-2 NSAIDs to gain approval and we have not used it as the others have been working well. I suspect that this medication works just as well as the others, though.

Narcotics


Narcotic pain relief medications have been used for a very long time. There are a number of these medications available with a wide variation in their pain relieving capability and in their potential for addiction. Fortunately, in veterinary medicine, addiction is much less of a problem than in human medicine for the simple reason that dogs and cats can't buy the medications themselves. It is still important to recognize that it can occur and to withdraw medications appropriately when there is a reasonable expectation that some degree of addiction may be present. Narcotic medications work well with other pain relief medications, especially the NSAIDs and combinations of these medications work better than either group alone. There are categories of narcotics and some of them work in ways that make it a bad idea to use one right after another or to use two antagonistic narcotics at the same time. This is mostly a worry for your veterinarian when prescribing narcotics but it is important not to use these medications without the advice and supervision of a veterinarian.

Narcotic medications are almost all controlled substances, meaning that they are regulated by the Drug Enforcement Agency (DEA) as well as the Food and Drug Administration (FDA). Veterinarians have to purchase and maintain special licenses to use these drugs and must account for every instance in which they are used. When it becomes common knowledge that a veterinary practice uses and stores narcotics there is a higher risk of robberies for the clinic. Due to these issues there are veterinarians who will not stock and use narcotic medications. In general it is possible to practice without narcotics but in many instances it severely restricts the ability to properly treat a patient's pain. While I can really understand why veterinarians would want to avoid the use of this category of medications I also think they are important enough in the treatment of painful conditions that it is worth finding a veterinarian who is willing to put up with the paperwork and minor risks of handling these medications if your pet has a painful condition that won't respond to drugs that are not controlled substances.

Morphine is the narcotic most people are most familiar with. It is a very good pain relief medication and it is definitely worth considering when a pet has severe pain. Morphine works consistently and reliably in dogs. It sometimes causes pretty severe reactions in cats in which extreme excitability occurs. This can be a major problem if the cat's condition can be worsened by uncontrolled activity, such as a cat recovering from orthopedic surgery. One drawback of morphine is that it must be administered frequently.  Morphine frequently causes vomiting and can produce sedation. At higher doses constipation can be a problem with long term use. There are sustained release morphine preparations that work well in dogs but which are much more expensive and are closely monitored by pharmacies, making it uncomfortable for pet owners who have to purchase these medications, at times. If your pet needs pain relief and it is only possible to give medications twice a day these are worth considering, despite the hassle.

Outside of the United States one of the most commonly prescribed narcotics is pethidine, which is generally known in the U.S. as meperidine (Demerol Rx). In the U.S. the use of meperidine is less frequent, which may be due to relative availability as meperidine is a controlled substance in the U.S. There is some question about the duration of action of meperidine in dogs and cats as most studies suggest that it provides approximately one to two hours of pain relief. It is supposed to work well in combination with NSAIDS and this effect may be due to good short term pain relief. In many cases if severe pain can be dampened, even for a short time, it will make pain easier to control over the long term.

Codeine and hydrocodone are used frequently in veterinary medicine. These are not nearly as potent for pain relief as morphine but they make a very good combination medication for use with NSAIDS. Vicodin (Rx) is a mixture of hydrocodone and acetaminophen, which can be used safely in dogs. Codeine/aspirin combinations are also available. These combinations are not acceptable for use in cats. We usually base our dosing on the hydrocodone or codeine portion for combination medications.  Hydrocodone can be used in cats if it is the sole ingredient.

It is pretty common in veterinary medicine to dispense butorphanol (Torbutrol Rx) for pain relief, especially in cats. While this is definitely better than no pain relief at all there are limits to the effectiveness of butophanol for chronic pain, as its effects only last for one to two hours in most dogs and several hours in cats. In addition, increasing the dosage of this medication can sometimes lessen its pain relieving effects rather than increase them.

Buprenorphine is a narcotic that is not approved for use in dogs or cats even though it is used fairly often. It provides a longer duration of pain relief than butorphanol. It doesn't come in an oral form but the injectable form is given orally in cats as it is tasteless and works well as an oral solution.  This medication is rapidly gaining favor in the United States as the preferred narcotic for use in cats.

Fentanyl is usually used as a transdermal patch (Duragesic Rx) in dogs and cats. It provides long term pain relief by constant absorption through the skin from the patch. It is surprising, but most pets will leave these patches alone. Despite this it is important to prevent the pet from ingesting the patch as this can provide an oral dosage high enough to cause coma or death. It is important to recognize that there is a delayed onset of effect when using the patches. In dogs it takes about 12 hours to achieve good pain relieving dosages and in cats it takes a minimum of five hours. The effective life of the patch is about 3 days in dogs and up to 5 days in cats. The pain relief from these patches is considered to be moderate, especially in dogs. For this reason it is often necessary to use them as a constant provider of pain control but to supplement them as necessary with a compatible narcotic or an NSAID.

 


Other Pain Relief Medications


Tramadol (Ultram Rx) is a a pain relief medication that has similar effects to narcotics but is not actually a narcotic compound. It is useful in both dogs and cats for long term pain relief. This is a medication that can be used by veterinarians who are adverse to using controlled substances but who wish to provide some benefits associated with narcotics. The recommended dosage in dogs is 1 to 2mg/kg every 12 hours but doses up to 5mg/kg and dosing intervals as short as every 6 hours have been used when necessary in dogs without major reported adverse effects. In cats the recommended dosage is usually 1/4th of a 50mg tablet per cat every 12 hours.

Acetaminophen (Tylenol tm): cats can not process acetaminophen at all and it is unsafe in cats at any dose. Dogs tolerate acetaminophen without problems at dosages up to about 25mg/lb every 8 hours but there is a lot of controversy over how well this medication works in dogs. Most veterinary pharmacologists seem to suspect that it doesn't work at all. It is often given in combination with hydrocodone as the combination medication is less expensive than hydrocodone alone.

Gabapentin (Neurotin Rx): is a seizure control medication that seems to suppress chronic pain. It is expensive and we have not had a situation in which we had to use it so I have no personal experience with it. The recommended dosage is 1 to 4mg/kg every 12 hours in dogs and every 24 hours in cats. In humans gabapentin is reported to provide additional pain relief in extreme pain situations in which narcotics such as morphine aren't potent enough alone.

 

Antidepressants

It might sound strange to include antidepressants in the pain relief category of medications but there is reasonable evidence that some of these medications do help to relieve chronic pain. It is plausible that some of the antidepressant effect may in fact be pain relief, at least in some patients.

The antidepressant that is most commonly used as an aid in controlling long term pain is amitriptyline (Elavil Rx). This medication has been used for some time in pets as an aid in controlling behavioral problems, for its antihistamine effect in skin disease and now for chronic pain relief. It is used in combination with pain relief medications in almost all cases and it seems to reduce the amount of pain relief necessary in many patients. In dogs amitriptyline is usually dosed at 1 to 2mg/kg every 12 hours. In cats the dose is usually 2.5 to 12.5mg per cat given once a day, usually at night.

Imipramine (Tofranil Rx) is another antidepressant that seems to help with chronic pain. In dogs it is generally dosed as 0.5 to 1mg/kg every 8 hours. In cats the dose is 2.5 to 5 mg/kg every 12 hours. We have no clinical experience with imipramine for pain but we have used it in dogs for urinary incontinence and one of those owners noticed that her aging Lab was more mobile while on this medication.

 

Acupuncture


Acupuncture seems to work well for some patients for relief of both acute and chronic pain. In studies somewhere between 50% and 90% of patients who have acupuncture still need additional pain relief but less potent medications can sometimes be used or lower doses of stronger medications. There is some concern that a tolerance to acupuncture may occur in chronic pain where it is necessary to repeat treatments regularly and that owners might miss this if they are not looking for it. Acupuncture is not available everywhere but it is an option to consider when pain is not responding well to medications or when medications are undesirable for some reason, such as an adverse effect on disease conditions already present.

 

Corticosteroids


Most veterinarians and veterinary clients don't view corticosteroids as pain relief medications, for the primary reason that they provide very little actual pain relief. On the other hand, they are the most potent anti-inflammatory medications available and often it is inflammation that is causing the pain in the first place. Corticosteroids have a great number of side effects, including weakening cartilage in joints. However, there is a time in arthritis when there really isn't much reason to worry about cartilage in the joints anymore because it is already severely damaged. This is also often the time when a pet owner is considering euthanasia because a pet isn't getting around well enough to enjoy life at all. Using corticosteroids at this time makes sense. After all, if the alternative is euthanasia, what side effect will change that scenario?

 

Pain Relief Without Medications


For pain caused by arthritis and back pain there is good evidence that weight reduction to ideal or even slightly below ideal weight for the dog's size will lessen chronic pain quite a bit. In some studies weight control has worked as well as the NSAIDs for control of chronic pain from these types of conditions. It can be hard to get your pet to lose weight but the benefits are definitely worthwhile.

Don't overlook the value of simple touch and of caring compassionately for pets experiencing pain. It really does help to massage chronically sore limbs. Ice packs can be very helpful for some types of surgical pain and for acute injuries both in limiting pain and speeding the healing process. Warm compresses can help with chronic pain, especially arthritis pain. It can take some coaxing to get a pet to accept these types of care but it is often worth the effort. A soft bed seems to help some dogs with hip dysplasia or elbow dysplasia quite a bit, although it is important that it still be thin enough that they can get up easily from it. Just showing a pet sympathy can help a great deal with acute pain and probably works pretty well for chronic pain, as well.

Dr Mike Richards, DVM 12/02/2007

 

Pain problem in  young Akita


Question: Hi Dr. Mike,

I have a 1 yr old Akita male (neutered) with a strange problem.  A couple of months ago, he was limping and I noticed a blister on his right rear paw.  This was after a couple of days of hard play, so I had him rest for a week and the blister seemed to heal.  Now, he will not allow me to touch either of his rear paws.  He screams out in pain and will actually reach around and grab my hand to remove it (he never bites.)  Now, he is starting to exhibit the same behavior anytime he is touched on his tail, or near the base of it.  I have tried to look at his skin and he does have flaking, similar to dandruff but no vesicles or blisters of any  type.

Any ideas?  He is otherwise a healthy happy dog.

Thanks, Doanielle

Answer: Doanielle-  

I can't relate all of the signs that you are seeing to any particular condition, but it seems like there are a couple that you might want to work with your vet to rule out.

Akitas have been reported to have a juvenile onset polyarthritis condition that might cause the limping and the pain upon being touched. This condition was reported in an article in the AVMA Journal in 1991 by Dougherty, et al. It is reported to resemble rheumatoid arthritis and to respond at least partially to immunosuppressive medications.

There are some case reports of Akitas with neutrophil function problems similar to a disorder seen in Weimaraners, in which there is a high susceptibility to joint infection and to infections in general due to immune deficiency caused by the poor neutrophil function. I think that your puppy would probably be sicker if this was present but if other problems have developed this might be something to think about, as well.

Akitas are reported to be susceptible to a condition that is currently called uveodermatologic syndrome, which causes eye inflammation and skin disease, usually including loss of pigment of the nose and the areas around the eyelids and often affecting other areas of the skin. If your puppy is showing any signs of eye problems it would be worth considering this possibility. This condition was formerly referred to as Voyt-Koyanagi-Harada (VKH) like syndrome as a similar but different problem occurs in humans that has this name. Checking carefully for signs of eye inflammation can be helpful in identifying the presence of this problem.

There are several pemphigus disorders of the skin that affect dogs, too. These are immune mediated skin disorders that frequently cause skin blistering (although many people miss this sign) and tend to affect the feet, lips, nasal planum, eyelids and other areas in which normal skin meets specialized skin. These are best diagnosed with skin biopsy of the affected areas.

It seems possible that there is a recognized disorder in which there is just pain associated with skin contact, as this does occur in cats, but I am not aware of a disorder that has this sign, by itself, in dogs.

It is also possible that this is a behavioral sign. Dogs that consider themselves to be dominant in a family may avoid being touched or may display behaviors such as mouthing the touching hand. If this is the case, you may see increased signs of aggression associated with these actions as time goes on. It is just another thing to think about.

I hope that this helps some.

Mike Richards, DVM 10/15/2001    

Long term pain control  


  Question: Hats off to you , for addressing the issue of pain control in animals. I was a vet tech in an emergency   room 20yrs ago, and I have been working as a emergency room  RN for the last 12 yrs.I am suprised   that aspirin is still ahead of the game, that is what we used 20yrs ago. I have 5 dogs, and I have watch   them suffer needlessly, I also tried the new anti-inflammatory with little success.

  My question is this, my golden retriever has severe hip displasia, I talked with my vet about the use of   elival for chronic pain, that has been popular with people, he was not aware of this use but was willing   to try it. She is on 100mg of amitriptylin qd. I have notice, she rest for longer periods, not breath as   heavy, or pace allot,she is now going up the steps, but I can still tell she is having some pain, I was   wondering if we could up her dose a little more, the veterinarian was not sure on what does to start her   on, so this is all trail. I am lucky that my vet is so open minded.Any suggestions or comments?   Neurontin is now the drug up in running for pain control, but its primary use it for seizures in people.

  Sincerely Tina  

Answer: Tina-

I found one of the articles that I was looking for on pain control. It actually addresses pain control in cancer patients but there is a section on bone pain that is probably applicable to osteoarthritis. I still think that there is another article that more specifically addresses chronic osteoarthritis pain among my journals but I can't find it. In several months these will be indexed in the online databases and I might be able to find the reference that way since I haven't been able to find it by looking through the journals stacked around my desk.

There is evidence for pain relieving effects as an enhancement to analgesics in dogs for amitriptyline (Elavil Rx) and for imipramine (Tofranil Rx). The recommended dosages in "Small Animal Clinical Oncology" by Withrow and MacEwen is 1-2mg/kg every 12 to 24 hours for amitriptyline and 0.5 to 1mg/kg every 8 hours for imipramine. The effect is postulated to be partially due to seritonin re-uptake inhibition  so it is possible that fluoxetine (Prozac Rx) and similar SSRIs would also provide similar enhancement to analgesic effects.

I found a case report on the use of gabapentin (Neurontin Rx) for pain relief due to neuropathic pain. This is apparently the most common use for this in people but isn't yet a common use in pets. Pain associated with shingles and with diabetes are examples of neuropathic pain in humans. I do not know for sure if it would be helpful in chronic osteoarthritic pain, or not.  I don't see any reason not to try it if you find yourself looking for something different than amitriptyline.

Carprofen (Rimadyl Rx) has been the most consistently beneficial non-steroidal anti-inflammatory medication for the pain associated with osteoarthritis in our practice. We have reasonably good success with etodolac (Etogesic Rx, Lodine Rx) as well. I usually start out with aspirin first but it sounds like you are beyond that point. When carprofen and etodolac don't work well enough we usually add an opiod medication. I usually start with hydrocodone or codiene but we use morphine in some dogs. I like the sustained release morphine (MS Contin Rx) really well but it is expensive compared to morphine. The difference in using the medications is that morphine probably only works 4  hours or so and MS Contin works for 8 to 12 hours. For many dogs several hours of pain relief is enough to make the day livable, so there is some value to regular morphine twice daily, if that is all that can be managed. We try to hold off on opiod medications until late in the arthritis process but they can be used for short terms, intermittently, to provide a period of really good pain relief to cut down on the depression factor that seems to come with chronic pain.  In dogs, since we control the medication dosages, addiction is probably less of an issue than it is in humans, too.

Ancillary treatments that might help include glucosamine and chondroitin administration (500mg/day and 400mg/day per 25 lbs of body weight), omega n3 fatty acid administration (3V Capsules tm, for instance), and Vitamin E (400 to 2000U per day).

Keeping weight down to the ideal weight, or slightly below it, probably helps more with arthritis than most medications. Moderate sensible exercise on a regular basis seems to help a great deal, too.

I hope that this information is  helpful.

Mike Richards, DVM 7/2/2001  

Intermittent pain in schnauzer pup


Question: Dr. Mike, We're having a strange and unsettling problem with our 6 month old miniature schnauzer pup.  He has not been neutered (yet), is about 10lbs, and has been eating Eukanuba lamb and rice puppy food since he's was weaned.  Other than this problem, he appears to be in great health, and is doing well.

Every once in a while - but sometimes as often as twice a day, Milo will be just standing there, and he will cry out and tuck his rear under like he's been stuck with a pin.  He usually looks back at his rear and curls around toward his hindquarters.  It appears to us that he is in pain, and appears very surprised by the pain that he is feeling.  At other times, although not in any apparent pain, he sits down suddenly and curls around to either bite or lick at his rear.  We have not particularly noticed that this happens at any particular time, such as during defecation, etc.

He has had some loose stools lately, and we have had trouble housebreaking him.  He often defecates in his crate and in the house.  In comparison, he rarely has urination accidents in the house, and never has had them in the crate.

We have taken him to the vet, who has checked his prostate (with the finger), prescribed an antibiotic and stool hardener (in the same med), checked his anal glands (clear)and requested that we change his food to Hill's Science Diet Lamb and Rice.

We don't know if the loose stools, housebreaking challenges, and crying out are related, but our vet offered us no explanation as to why he is crying out like this.  He has been checked for worms twice (via fecal float), but was cleared.  The vet has suggested that we consider x-rays, but we're skeptical.

What could be causing this pain?  Do you think that it's his anus, or maybe his testicles?  Do you think that this is related to the housebreaking issues and the loose stools?  We're very upset about this, and would greatly appreciate any help that you can provide.

Sincerely, Mark and  Nina

Answer: Mark and Nina-

Your vet has done the things that I would have tried first. This sort of pain occurs sometimes when anal sacs are impacted or infected. Since this is a common problem, it is one of the first things to rule out.

Prostate disease would be unusual in a dog this age but it is easy to check on the prostate while preparing to express the anal sacs so that is a good thing to do, too.

Allergies do produce this symptom in some dogs and it is reasonable to try to rule out this possibility, too. Using a hypoallergenic diet, such as a lamb and rice diet or other novel protein (duck, salmon, egg, etc.) to be sure a food allergy isn't present rules out one type of allergy. It is a very good idea to use a reliable flea control product, such as Frontline (Rx) or Advantage (Rx) to be sure that flea allergy is unlikely.  Finally, there are a few dogs that can  have inhalant allergies (atopy) even at this young age but that is also an unlikely problem at this point.

Spinal problems, such as cauda equina syndrome, which is pressure on the nerve roots leaving the lower spine, can lead to sharp pain that is hard to localize. Sometimes it is possible to recognize signs of this disorder on X-rays and sometimes it isn't.  In older dogs, disc disease might cause this type of sign but this would be really unusual in a dog in this age range.

Infections around the base of the tail, in the tail folds, in the perianal region or in the mucosa right at the edge of the rectum (perianal fistulas) can cause this type of problem.

I have always wondered if this symptom could be a sign of phantom pain in the breeds in which tail docking is done, such as schnauzers. Obviously, without being able to ask dogs what they are feeling, it is hard to prove or disprove this possibility. I haven't seen any mention of this possibility in the literature, so it may just be a figment of my imagination that this could, or would, occur. As far as I know there are no pain relievers that work well consistently for phantom pain but some people think that acupuncture helps and narcotic pain relievers such as morphine or fentanyl may also be helpful.  It is tough to decide to use something as potent as these medications for an intermittent pain problem, though.

I wouldn't think that testicular pain was highly likely but would not be able to rule it out completely, either.

I think that it is worth continuing to look for an identifiable problem. It may take several tries to identify an intermittent problem like this, so keep working with your vet.

Mike Richards, DVM 8/7/2000      

Pain control in older dog - Muffy continued


Q: Dr. Mike,

Thanks for the quick response. We Started Muffy on Anipryl on Thursday.

Another problem has surfaced. Last Friday Muf fell down the stairs and bruised her already weak back legs. She currently takes 100 mg of Rimadly daily.

She seems very very sore. Would it be OK to supplement her with some aspirin too until she gets over this?? Muf is about 55 lbs (Springier Spaniel)

Also, if the Anipryl doesn't work would it be OK to try Prozac??

Thanks Dr.Mike, you are a life saver. As you can see we love Muffy more than anything and want to make her as comfortable as possible.

Rick & Darleen (Muffy's Mom & Dad)  

A: Rick-

I would be very hesitant to use aspirin and Rimadyl at the same time. Both of these medications are non-steroidal anti-inflammatory drugs (NSAID) and as such, they have the potential to irritate the gastric and intestinal linings. While Rimadyl is formulated to minimize this risk it still has some potential to cause irritation and the effect might be cumulative with aspirin.

I think that there will be more and more information available on helping older dogs through age related problems with medications but currently there isn't a lot of concrete information on drugs like fluoxetine (Prozac Rx) and their effect on these problems. There are fairly well established dosages for this medication, though, so trying it seems reasonably safe if Anipryl (Rx) is not beneficial.

If Muffy will allow you to use hot or cold compresses on the sore areas you might that they are beneficial. Just a heating pad set on low that Muffy can choose to lay on if she wants to might be beneficial. Sometimes gently massaging sore areas seems to help, too. Pets are like people -- sometimes the little things help as much as medications. There are several commercially available heated pet beds or heating elements designed to be safe to use for pets.

It is possible to combine narcotic pain relievers, such as butorphenol (Torbugesic SA, Rx) or hydrocodone (Hycodan Rx) with an NSAID, to get more pain relief. We have found this combination to be helpful in many instances for pain that either medication alone just can't quite control.  

Mike Richards, DVM  

 

Pain control with complicating illness - Shih Tzu


Q: Dr. Mike. I desperately need your advice since my dog is in a lot of pain and my vet seems to be running out of solutions...I adopted my dog 4 yrs. ago from the shelter and I think my dog may be around 12 yrs. old. He is a Shih -Tzus with very bowed front legs and weighs 16 lbs. About a month ago my dog started having a hard time getting up in the morning because of pain in his hips . I treated him with asprin for a week and his condition improved . My vet x-rayed his back legs and discovered my dog had knee joints which protrubed out of the sockets and had very bad hip dysplasia . He prescribed Rimadyl and his condition improved. When my dog was on either asprin or Rimadyl he was able to walk and was peppy most of the time. A week ago my vet discovered from blood tests (ACTH response test) that my dog had Addison's disease. He prescibed FLORINEF (0.1 MG twice daily) and Prednisolone (5 mg per day ). The Rimadyl was discontinued and this is when the problem got worse. He has been on the Florinef and Prednisolone and now he can barely walk and is very weak and doesn't want to move. Also he had diarrhea today. Two days ago in addition to the Florinef and Prednisolone my vet also gave my dog his first shot of Adequan and an anti-inflammatory injection and put him on a dextrose IV for a few hours. Two days later after these injections and IV, my dog seemed to have taken a turn for the worse and my vet is out of answers. In my view, my dog seem to take a turn for the worse once the Rimadyl was discontinued and the treatment for Addison's disease started. Now my dog does not want to get out of his bed and he seems to be in a lot of pain. Please help me. Could the results from the ACTH test be wrong? Is the Prednisolone helping with the hip dysplasia and does it work as effectively as Rimadyl? What else can my dog be prescribed for the pain in his hips in light of the Addison's disease? I was told that my dog cannot take asprin or Rimadyl with the Florinef and Prednisolone. Please help my dog is very sick and I am running out of solutions. Up until today my dog has been eating ok and has been drinking water, but I have to carry him outside to go to the bathroom and he cannot walk very well. My vet does not want to put him to sleep because he thinks there may be some hope. Thank you for any advice you may have.

A: JCJC- I am sorry for the delay in answering your question. To the best of my knowledge there is no reason not to use apirin or carprofen (Rimadyl Rx) in conjunction with fludrocortisone acetate (Florinef Rx). However, there is reason to believe that concurrent administration of glucocorticoids such as prednisone and non-steroidal anti-inflammatory medications (NSAIDS) such as aspirin or Rimadyl does increase the chance of gastrointestinal effects including ulceration. For this reason, most vets are reluctant to use these medications together. There is an FDA approved medication that is a combination of aspirin and methylprednisilone, though, called Cortaba (Rx). I always thought it was odd that there were warning against using these products together and an approved medication containing both.

In desperate situations it is worth considering desperate measures and I don't think I'd be afraid to use Rimadyl with the other medications, especially since it is less likely to have GI effects than other NSAIDS. The manufacturer of Rimadyl, Pfizer, recommends against this combination at the current time if you want a third opinion.

I think sometimes lab tests are in error. The clinical signs you mention could be seen with Addison's disease, though. In most cases it is a good idea to rerun the tests to gauge the effects of the medications so your vet may have already done this. If the results were surprising it may be that there is a need to rethink this diagnosis but the only way to tell is to check.

Mike Richards, DVM    

Pain relief - NSAIDS and Nutriceuticals


Q:  Can any NSAID other then Rimadyl be used in dogs? This stuff is outrageous in price. Have you any experience with Cytotec in conjunction with these drugs in dogs? Steve

A: Steve- I still like aspirin a lot. Prior to the approval of carprofen (Rimadyl Rx) we used aspirin in conjunction with hydrocodone with good success in several patients in which aspirin was not sufficient for relief of pain. Some vets use phenylbutazone and believe that it works better in many patients. This hasn't been my experience but I can't argue with their perception. Other alternatives include Arquel (Rx), whose generic name escapes me at the moment and the whole range of glycosaminoglycosans, including Adequan (Rx), Glycoflex (tm), Cosequin (tm) and others. These "nutriceuticals" are considered to be helpful by many people. Little things like providing a warm or soft bed, spending a few minutes massaging sore legs or ensuring regular moderate exercise can all help. If your dog is overweight the single best thing you can do is to help him or her lose weight. This does more to relieve the pain associated with arthritis than medications in many instances. Rimadyl (Rx) is fairly expensive, especially for a medication meant to be used on a continuous basis but it works well and people continue to buy it so I think the price is likely to stay about where it is for awhile.

Mike Richards, DVM  


Pain control in older dog - bite wound from dog attack


Q: My 15 year old german shepherd was recently attacked by one of my other dogs and sustained an injury to her shoulder - the other dog bit her skin and was shaking her violently, which my vet said pulled a large area of skin loose, creating a large (10"x8") pocket between her skin and whatever is underneath it. He prescribed 60 mgs rimadyl to be given twice daily for the pain associated with this injury. In reading the info on the drug on your site, it appears that this drug is indicated for arthritis, not soft tissue trauma. What do you think about this application? She may or may not have some arthritis, anyway. She does have some trouble getting up, but she also has a very large (3/4 the size of a football) benign fatty tumor on the left side of her back, just forward of her hip, which throws her off significantly, making it hard to determine, I guess, if her difficulty is due to arthritis or just due to the weight/size/location of her lump. She doesn't seem to be in any pain from the injury since she's been on the rimadyl, and she does seem to be able to get up and down just as well as before the injury. Originally, I came to your site to see if there was any reason to be concerned about her getting "hooked" on the rimadyl, which I assume, again from reading your info, is not a concern.

A: Nuhat-

Rimadyl (carprofen) is currently being evaluated (or recently has been) at several of the veterinary schools for uses such as traumatic and surgical pain. So far, the results look very good. Your vet should be commended for considering your shepherd's pain - many vets forget about the need for pain relief from time to time. As far as I know there is no danger of addiction, as you have surmised.

Hope she feels better now.

Mike Richards, DVM  

 

Pain control


Q: I have a black lab eight 1/2 years old. He has been diagnosed with arthritis and seems to in pain and sluggish. He has been to the vet, but I am concerned about putting him on pain killers and am seeking a homeopathic remedy. do you know of any thing that I can do. Waxer is a very happy and playful dog, my fear with pain killers is that it might help his pain but he will not be able to enjoy the high quality of life that he has in the past. Is this true? Can you help me?

A: I think that pain control does increase the quality of life. This is especially true if your dog tolerates non-steroidal anti-inflammatory medications well. Aspirin is inexpensive and very effective. It causes gastrointestinal upset in a few dogs (probably about 1 in 10 or so) and can not be used in those dogs. Carprofen (Rimadyl Rx) is less likely to cause GI upset, is a more potent pain reliever but costs significantly more. It would be worth using one or the other of these medications if possible.

In addition, there are many people who feel that their dogs benefit from the use of glycosamines such as Cosequin (Rx), Arthroflex (Rx) or other similar products. Adequan (Rx) is an injectable version of these medications which seems to be more beneficial for some dogs. Vitamin E can be anti-inflammatory and large dogs will usually tolerate doses as high as 2000IU/day.

Weight control, moderate exercise and providing a warm place to sleep are non-medical things that help a great deal with arthritis.

Good luck with this. Pain relief is valuable - don't rule out medicines known to be effective for this.

Mike Richards, DVM  

 

Beagle Pain Syndrome / Systemic necrotizing vasculitis


Q: Dear Dr. Mike: I have a 5-year-old beagle who was diagnosed 2 years ago with beagle pain syndrome. This diagnosis was made after several x-rays and a spinal tap failed to find any cause for severe neck and back pain, fever and shivering. She has been on Prednisone for the past two years which controls the symptoms. She takes 5 mg. every 3 days with 2.5 mg. on the days between. I'm concerned about the long term implications of her taking a steroid medication. When she saw a new vet after we moved, the new vet recommended taking 5 mg. of Prednisone every other day and alternating with Rimadyl on the other days in an attempt to let her system "rest" from the steroids. I'm not sure how well she will tolerate this (she's had some vomiting and appetite loss). While I will follow up with the vet on these reactions and possible drug interaction problems, I'd like to know if you have any ideas about any alternative treatments or medications and if you have any additional information on beagle pain syndrome. Thanks for your help!

A: It is a lot better if prednisone can be given on an every-other-day basis rather than every day. It often won't work in immune mediated conditions when given in this manner, though. When this is the case, the choice between a life of reasonable comfort that may be slightly shorter and a long life of intermittent pain seems to be an easy choice to make, to me.

I actually couldn't find a reference to "beagle pain syndrome" when I looked through my texts but I did find references to two conditions in beagles leading to chronic pain of the type you describe. The first is immune mediated meningitis and the second a condition known as systemic necrotizing vasculitis which can affect the small vessels in the spinal cord, leading to chronic pain. Both are thought to be immune mediated conditions and both are treated with prednisone. It is my impression that the immune-mediated meningitis is usually not a long term problem, though.

I don't know of anything else you can do in the case of the systemic necrotizing vasculitis problem except consider other immunosuppressive medications. Prednisone is generally considered to be the safest of these types of drugs, though.

This sounds like a bad problem. Your vet took the right steps to make a diagnosis and I can't think of anything else that might cause the symptoms you describe that wouldn't show up in the testing done.
Mike Richards, DVM 

,

Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...

 

Comments