VetInfo Digest
December 2002
Suspected Drug Reactions that Aren't Real
Client Errors
.. choose the right vet
.. control fleas
.. don't mislead the vet
..get emergency care
..food trials are good
..get a diagnosis first
..repeat lab tests
..go to the specialist
.. stay legal
Some Contact Information
This Month's Note:
This month Hill's (tm), manufacturer of dog foods and Heska (tm), manufacturer of veterinary laboratory testing equipment and supplies, have combined to put on a promotion. Heska has a new diagnostic test for early kidney failure in dogs that provides information on microalbuminurea, or early protein loss from the kidneys. This is thought to be an accurate diagnostic technique. Hill's makes a special diet, k/d (tm) which is meant to help slow the progression of kidney disease once it is diagnosed. As you can imagine, the sales of k/d might increase dramatically if a lot of dogs were discovered to have early kidney failure through routine screening for kidney failure.
It is unusual, but not unprecedented, for companies with complementary products to get together to put on a promotional campaign. Hill's is a very aggressive marketer and the promotional literature for this marketing campaign seems to suggest testing all dogs. It is very unlikely that this is a cost effective way of finding early kidney disease, though. If you wish to be cautious, there is probably no reason not to do this test. Remember to be reasonable about any positive results in a dog that appears to be normal, though. Recheck after a couple of weeks to ensure that the test result is consistent. Make sure there isn't some other source of inflammation in the body, such as dental infections, persistent skin infections or inflammatory bowel disease. If nothing can be found , then it might be time to think about using k/d or similar diets.
If signs of kidney disease are present the test obviously makes sense. If your dog has known kidney disease, this test may help to determine the response to treatments and to help evaluate prognosis over time.
Suspected Drug Reactions That Probably Aren't
The category of medications which receive the most bad press over adverse reactions are medications which are given on a chronic basis. This includes the monthly heartworm prevention medications, seizure control medications, flea and tick medications and medications for chronic pain. When a medication is being given on a regular basis it is inevitable that other illness will occur while a pet is taking the medication. This makes it extremely difficult to separate adverse events related to the medication from adverse events that have nothing to do with the medication.
Monthly heartworm medications work by killing baby heartworms that have accumulated in the dog or cat for the thirty days prior to the time the medication is given. The heartworm prevention medications are present in the body for about 3 days although there is some variation in this. So the medication is exerting an effect for approximately 36 days out of the year. This is about 10% of the year. Due to this, other illnesses will occur during the same time period. Inevitably, some of them will seem like they are related to the administration of the monthly heartworm medication.
To get some idea of why this can be very confusing, think about the dangers associated with the month of October. This month takes up about 8% of the year. If someone became concerned that October was harmful to dogs it would be relatively easy to show that illnesses occurred during this month and that some of them were serious enough to cause the death of affected pets. Since we are used to the idea that October comes about every year and that it is just a measure of time, we don't associate illnesses with it -- but a very persuasive case could be made that it does cause problems if the only consideration is the coincidence that a disease occurs in October.
When medications are given chronically, the only people that see the effects of the medications spread out over a great number of pets are veterinarians and other people working with groups of animals. Pet owners only see one pet and so illnesses that occur in close proximity to the administration of the medication can easily seem to be related. It is important not to forget about the possibility of sheer coincidence, though. When studies involving multiple pets fail to show that problems that arise during administration of a drug are directly related to the drug it is generally safe to assume illnesses occurring in an individual patient are just coincidental. Unfortunately, a pet owner looking for an answer as to why their pet is having a problem often has a hard time believing that the medication was not the direct cause. Humans appear to be naturally inclined to believe in cause and effect relationships when events happen in close proximity.
To some extent, this same logic applies to vaccinations. The immune system responds to antigens (substances that it feels the need to attack as foreign material) all the time. It is reasonable to assume that there is exposure to many of the diseases that pets are vaccinated for, on a fairly regular basis. When a pet with adequate immunity is exposed to a wild virus or bacteria the immune response is approximately the same as it is to a vaccination, although the adjuvents in vaccinations may prompt a more vigorous immune response than exposure to a few wild virus particles. However, the bottom line is that a pet's immune system is being stimulated by environmental stimuli frequently and it is extremely hard to differentiate the effect of these sorts of events from the stimulus of the immune system from routine vaccinations. Therefore, it is questionable whether it will ever be possible to tell if there is a link between routine vaccinations and disorders such as hypothyroidism in dogs, hyperthyroidism in cats or other hormonal or immune system disorders, with the possible exception of immune mediated hemolytic anemia, which does seem to occur slightly more frequently in the month following vaccinations in dogs.
At the present time there are is no proof that I know of that long term use of heartworm prevention medications or monthly flea control products has a harmful effect on dogs or cats in any way.
Seizure control medications do have specific adverse effects associated with their use, with liver damage being the greatest risk.
There are risks associated with long term use of pain relievers such as carprofen (Rimadyl Rx) and etodolac (Etogesic Rx) and it is necessary to balance the need for long term pain control against potential risks. Carprofen causes severe liver damage in a very small percentage of patients and etodolac causes tear deficiency problems in a small percentage of patients. These are the known severe risks associated with these medications. Other suspected complications are less likely.
It may never be possible to know for sure whether vaccinations increase the risk of some immune mediated diseases and hormonal conditions but there is only the slimmest of indications at this time that these effects occur as a direct result of vaccinations. Vaccine site sarcomas (cancer) in cats has been proven within reasonable doubt to occur in a small percentage of cats and immune mediated hemolytic anemia does occur more frequently in dogs after vaccination than among dogs in the general population. These effects do not diminish the importance of vaccination but they are reasons to look closely at how long vaccines provide protection and to adjust vaccination schedules accordingly.
Common Client Mistakes
In an early issue of the VetInfo Digest I wrote about the most common mistakes made by veterinarians. There are also some mistakes that pet owners seem to be prone to. Avoiding these common mistakes will make it more likely that your pet will enjoy better health and will be more likely to have a good outcome when health care is necessary.
Choose the Right Vet
Veterinarians are most often chosen based on their proximity to the veterinary client's home. This indicates a low level of thought about what the veterinary - client relationship means in the care of a pet. There are many possible mismatches between veterinarians and clients but the worst ones occur when the client fails to recognize that the veterinarian is providing a different type of care than they hope for and when communication styles just don't match well enough for the client to understand information their vet is trying to convey.
Clients who want the best care for their pets should find veterinarians who want to provide the best quality care for pets. While this sounds simple, it often is not. There are many veterinarians who are more likely to provide for their veterinary client's needs than to advocate strongly for the pet's needs. This can happen when the veterinarian is primarily interested in pleasing people, when a veterinarian is uncomfortable with any level of confrontation and even in a few cases as a strictly business attitude. A client who is getting what he or she wants and hearing what he or she wants to hear may fail to recognize that they are being serviced well but their pet might not be. On the other hand, a veterinarian who is only interested in the pet's perspective may well put off even dedicated pet owners who simply can not afford expensive care or who need to have better explanations of their pet's problems than a non-communicative veterinarian can provide. Pay attention to what your vet is saying and how it is said. In most cases, it is possible to determine whether your vet is trying to please you or trying to tell you what is best for your pet.
In some cases clients seek specific types of care, such as homeopathic oriented medicine, or a veterinarian who is experienced in Chinese herbal therapies. In other cases, clients want a veterinarian who is willing to come to their home or a veterinarian who will give deep discounts to clients with multiple pets. These types of goals are pretty easy to satisfy, simply by asking appropriate questions. If you fear modern medicine and want your vet to use therapies such as homeopathy or herbal therapies, don't expect your vet to change to suit you. Find a vet who is interested in these therapies. It takes a great deal of time and effort to study more than one form of medicine and everyone is better off if the client just takes the time to find a vet whose interests in medicine match their own.
Control Fleas
Fleas are a major problem for both dogs and cats. Failure to properly control fleas is probably the number one cause of skin disease in pets. This may sound like an outlandish claim but I am nearly certain that it is true. Prior to the time that the good quality monthly flea prevention medications became available we treated at least three or four times the number of skin disease cases that we treat at the present time.
Make sure that you are using a product containing one of the following ingredients: fipronil (Frontline tm, Frontline Topspot tm), imidocloprid (Advantage tm), selamectin (Revolution Rx) or lufenuron (Program Rx, Sentinel Rx) in combination with adult flea control such as nitenpyram ( Capstar Rx). Use flea control medications as directed by your veterinarian for the flea season in your area. Monitor for fleas, even though you are using these medications. In some cases it is necessary to also control fleas in the house, kennel or yard in order to control symptoms of flea allergy. Having a dog or cat with flea allergy, flea bite sensitivity or unexplained skin disease and not using adequate flea control products is a major mistake.
Do not assume that a flea control product is not working because a dog or cat continues to be itchy. I have a number of clients who have ignored other treatable skin diseases while they switched from one good flea control product to another, thinking that the itchiness must be from fleas that were not being controlled by medications. Once good flea control is established, itching is much less likely to be related to fleas and it is time to look for other causes.
There are times when the monthly flea control products will be overwhelmed by sudden increases in the flea population. This happened this year in my practice area because drought conditions made it hard for fleas to reproduce. When rains came this fall, there was an incredible explosion in the flea population. This caused some of my patients to have flea allergy problems for the first time in years. In most cases the flea population was under control again in a few weeks but some of my clients needed to use additional flea control products briefly or premise control products to get the flea population under control. This is an unusual circumstance but it is a good idea to actually look for fleas if you suspect they are present.
Don't Mislead Your Vet
If you don't tell your veterinarian you gave your cat Tylenol (tm) because you are embarrassed to, you might kill your cat. If you don't let your vet know that you gave your dog ibuprofen or indomethacin for its lameness because you had these drugs on hand, you might kill your dog. If your pet doesn't die, you might pay three or four times as much money for a correct diagnosis of your pet's condition as you would have if you had just told your vet that you had given these medications.
I have worked on ten or fifteen dogs or cats with bullet wounds who "never left the house alone". I have seen many cases of dogs and cats with injuries that could only conceivably have come from being hit by a car or truck whose owners insisted that it was impossible for their pets to have been in the road.
Perhaps the funniest recent example of this was a woman who brought her dog to me because it wasn't eating well. She proceeded to tell me how she wouldn't ever see another vet because I was the best, as I removed the sutures from a spay incision that I am absolutely certain I did not perform. When I pointed this out to her she said, "Oh, my husband takes her to his vet all the time." The surgery didn't appear to be part of the current problem but it clearly warranted a mention in the medical history, along with the fact that the dog had been treated for appetite problems several times previously at her husband's vet's.
Every now and then we have a client who comes to us to get a second opinion but neglects to mention that is the reason for the visit. I think some of them genuinely think they will get a more honest opinion from me if they don't mention that I'm the third veterinarian to see their pet and others think that it will make me angry they went to the other two vets first. I can't speak for all veterinarians, but it is far easier for me to figure out the next step in the diagnostic and treatment process if I know what the results of earlier therapies and test procedures were. In most cases, it also saves the client the cost of repeated testing for at least a portion of the previous test procedures.
Don't Hesitate to Seek Emergency Care
For some reason, many veterinary clients will not seek emergency care for their pets, even when it is necessary. Emergency veterinary clinics may not be as comforting to seek care from as your regular veterinarian, but they exist because veterinarians can't work 24 hours a day. Waiting for your veterinarian to be available can be a terrible mistake.
If you find yourself in a situation in which you are wondering if your pet needs emergency care it is best to assume that the care is necessary and just go to the emergency clinic or to call your vet and arrange to have your pet examined. It is true that most pets who are cared for at emergency clinics would have made it through the night without emergency care. It is also true that pet owners are not very good at determining when pets need care and when they don't. If your pet is bleeding and you can not control it, if your pet is having difficulty breathing, seizuring for more than five minutes or having other obviously life threatening signs call your vet at once. If you don't get an answer don't spend time calling back several times -- find a veterinary hospital that is open.
Know where the closest emergency clinic is. Make sure the phone number is available. If your veterinarian will treat emergencies at night find out how to reach your vet after regular clinic hours if it is necessary to do so.
Emergency veterinary clinics often require a deposit in advance before providing major services. Keep a source of emergency money available. Almost all veterinary clinics accept credit cards and keeping a small emergency cash supply on hand is a good idea for both pet and family needs.
While it is appropriate to seek emergency care anytime that you think it may be necessary, there are a few conditions that should be considered true emergencies. Severe respiratory difficulties, sudden weakness or paralysis, traumatic injuries, moderate to heavy bleeding that does not stop within three to five minutes, inability to urinate, seizures that last more than five minutes, known or suspected poisonings, bites from other animals and suspected heat stroke all warrant seeking emergency care.
Understand and Follow the Directions
Veterinary clients often fail to follow the directions given by the veterinarian for pet care. This is especially true for administration of medications and dietary recommendations (outlined in the next section).
I know that some of my clients take pills home that they know they can't administer. I try hard to remember to ask clients if they can give pills and usually we check to see that we can give a pill to a patient before prescribing them but inevitably there are times when we forget to do this. Don't take a medication home that you know you can not administer.
One of the major reasons for prolonged urinary tract infections is inadequate treatment of the first urinary tract infection. Cat abscesses often recur when antibiotics are stopped prematurely. When antibiotics are dispensed it is important to follow the directions and to use them for the full amount of time recommended by your veterinarian.
It is critical that you understand how to make adjustments to medications that require individualized dosing, such as insulin, corticosteroids, immune system modulators, thyroid supplements and other medications that require adjustments based on patient response. You must continue to ask questions of your veterinarian or your veterinarian's staff until you are absolutely certain that you understand how these medications are used. Do not leave the veterinary hospital with this type of medication until you are sure you understand what testing is required to monitor the medications and how dosage adjustments will be made. I know that some of my clients stop asking questions when they are confused enough to feel embarrassed or just become frustrated. This is a time when you have to put those emotions aside and keep asking questions until you really do understand how medications are to be used. It is too easy for your veterinarian to assume you understand and for poor communication to occur.
A Food Trial is a Good Idea
Food trials are substitution of a specialized diet for the regular diet for a period of time sufficient to determine if food sensitivities are contributing to a pet's problems. These are usually done to rule out food allergies as a cause of itching or persistent ear infections and to see if digestive problems are due to food sensitivities or allergies.
Of all the things that we recommend to our clients, food trials are among the hardest things to convince clients to do and they are the one thing in our practice that clients fail to do properly the most often.
Food allergies are probably not a common cause of itchiness in dogs. They appear to be more commonly associated with skin disease in cats. Therefore, when we recommend food trials we know that there is a very good chance they won't work. I think that this discourages a lot of clients. However, when it is possible to demonstrate that food allergies are the cause of a dog or cat's skin disease, it provides a method of treating the pet without medications that works very well. Simply stop feeding the foods that cause the itchiness.
Diarrhea and/or vomiting in both dogs and cats does seem to be related to food sensitivities and food allergies reasonably often. Whenever there is persistent vomiting or persistent diarrhea that does not respond to medical therapy, or relapses when medical therapy is withdrawn, it is reasonable to suspect food sensitivity and to test for it.
Food trials work best when home made diets are used but work reasonably well with the new hydrolzyed diets, such as Purina HA (tm) and Hill's z/d (tm) foods. A home made diet should consist of meat protein source that the pet has not ever eaten previously, if possible. Examples of meat proteins not commonly found in pet food include turkey, rabbit, venison, duck, alligator, salmon and eggs. The meat protein should be mixed with a carbohydrate source that is uncommon in pet foods. Rice used to work well but is less effective now that it is included in a number of pet foods. Potato and peas are alternatives to rice. The home made or commercial diet should be fed for a minimum of four weeks and most dermatologists and gastroenterologists recommend much longer food trials, with eight to twelve weeks being the range suggested most often at the present time.
The major problem with food trials is that a pet should not be allowed to eat anything other than the recommended diet for the entire food trial. This even includes avoiding flavored medications such as chewable heartworm prevention, flavored antibiotics, chewable incontinence medications and pain relieving medications. It is very hard for many pet owners to resist giving their pet food items that interfere with the food trial. Dog and cat treats, chew toys such as rawhide bones, table scraps and hunting prey can all interfere with proper food trials. If there are other pets in the household they must be fed the elimination diet or they must be fed entirely separately from the pet being tested for food allergies or sensitivities.
While I recognize that it is very hard to do a food trial appropriately, it often represents the only real hope of eliminating chronic diarrhea or vomiting and is useful in eliminating food allergies as a cause of itching and persistent ear infections. A pet with food allergies or food sensitivities whose owner can not, or will not, properly conduct a food trial is condemned to living with an uncomfortable condition for life. Working hard to provide a good diagnostic food trial for a couple of months is not an unreasonable task when the potential long term benefit is considered.
Get a Diagnosis First
I get some complaints about veterinary fees. However, I can tell you with absolute certainty that most veterinarians are very price conscious and will often attempt treatment for a pet's problem rather than asking veterinary clients to spend money on diagnostic tests. This is OK for minor acute illnesses that are likely to go away on their own or to respond favorably to therapy. It is less acceptable when dealing with chronic illnesses or conditions that are likely to require life long therapy.
If your pet has a persistent illness or if your vet is suggesting a medication that is meant to be used lifelong, it is important to have a good quality diagnostic process. Don't avoid testing procedures in these situations, even if they are fairly expensive or require going to an out of town specialist. Few things are more frustrating than treating an illness for a year or two, only to find out that you are treating improperly because a simple test wasn't done or because an effort to avoid complicated testing led to an erroneous diagnosis.
It isn't unusual for testing procedures to cost several hundred dollars at the onset of care for complicated illnesses. Often, clients will request that a portion of the testing procedures be postponed or eliminated from the diagnostic work-up. Sometimes skipping steps in the diagnostic process works out OK. In other cases, attempting to conserve $50 in a $300 work-up results in a failure of the entire diagnostic process and the necessity to repeat the entire process or at least large portions of it. If the ultimate goal is to get the correct diagnosis as quickly as possible, skipping testing procedures is a poor choice. Even when the goal is to get to a diagnosis as inexpensively as possible, skipping testing procedures works out badly often enough that careful thought should be given to just doing the job right the first time.
Not Allowing Repeated Testing Procedures
Doing the proper diagnostic tests the first time doesn't always mean that they won't have to be repeated. Veterinary assistants, veterinary technicians, veterinarians and laboratory technicians are all humans and once in a while humans make mistakes. Lab values that don't match the disease process should be repeated to ensure they are accurate. If they are accurate and they point in a very unexpected direction, it may be best to repeat testing to ensure that there aren't two problems. Some tests are just necessary to repeat more than once to ensure the best possible accuracy. Fecal examinations often have to be repeated to find the offending parasite, for instance. We have drawn blood because we were suspicious of liver disease and gotten normal lab results in several patients who had measurable, and in some cases severe, changes in liver enzyme levels in as little as four or five hours.
When a pet has a persistent illness it is often necessary to repeat lab tests to ensure they are still normal or to track changes in known abnormalities. It can be frustrating to pay for lab work over and over again, but it can also be the difference between good quality care and poor quality care. This is most important when the diagnosis that testing seems to be supporting does not match the clinical signs of the pet's illness. It is estimated that approximately 5% of reported lab values are inaccurate to some degree. Errors can occur in sample taking, labeling of samples, handling of the samples during transport to laboratories and at the lab itself. It is disheartening to have to run expensive lab tests more than once to ensure accuracy but doing so may clear up a difficult diagnostic dilemma even it turns out that an errant lab result is confusing the issue.
Go To the Specialist
Veterinary clients should never forget that there are veterinarians who specialize in particular areas of medicine. Board certified internal medicine specialists, surgeons, ophthalmologists, dentists, behaviorists and other specialists are available. When your veterinarian suggests seeking an opinion from a specialist it is best to follow that advice in most cases. This is true even if you have to drive several hundred miles to get there.
Behavioral problems seem to be the one set of problems that people balk most often about seeing a specialist for. This is really too bad, because behavioral medicine was not taught in most veterinary schools until recently and still is a minor part of the curriculum. In addition, behavioral specialists can often provide follow-up care by telephone, e-mail or letter. So even though it may be a long trip to the specialist for the initial diagnostic process, it is often unnecessary to make a great number of repeat visits. When you consider that an untreated behavioral problem is usually a life long problem, it makes sense to seek the best possible care at least once, even if it is difficult to do so.
Specialists in other areas can be helpful, as well. Try to be sure that you really are seeing someone who is an expert in their field. Board certification is a good indication that a veterinarian has taken the time to become an expert in a particular type of care. There are very good surgeons and veterinarians who are experts in other fields without being board certified. If your veterinarian has a lot of confidence in a local practitioner's ability to help your pet it is also a good sign. I wouldn't trust self proclaimed "specialists'", much though. For one thing, it is considered to be unethical for veterinarians to claim to be specialists in a field if they are not board certified in that field. A nonboard certified veterinarian may have a practice that is "limited" to a particular discipline, such as dentistry --- but they should not claim to be a specialist.
Many veterinarians feel that referring patients to a specialist is a risk. The client may not like the specialist and may then resent the vet for sending them. The cost of specialty care can be hard for clients to absorb and this may cause resentment. The specialist may think that the vet's initial diagnostic and treatment efforts were inappropriate and communicate this to the vet. For these and other reasons, most vets really think a pet should see a specialist when they suggest a referral.
Don't Ask Your Vet to Break the Law
Several times each month clients ask me to break the law. They want prescription medications for a pet I haven't seen, they want heartworm prevention medications when we don't have a negative heartworm exam on file, they ask me to provide a rabies certificate for a pet that another veterinarian vaccinated or to certify that I have examined a pet that I haven't seen, that is already on the way to Bermuda without health papers.
Veterinarians operate under a mix of local, state and federal laws and a few bureaucratic regulations with the weight of law. Most veterinarians want to have the option of a long career. When your veterinarian advises you that it is necessary to examine your pet prior to dispensing a prescription drug it is not only a good idea, it is a legal necessity.
Contact Information for Some Products We are Frequently Asked About
Cushioning clothing for treating elbow calluses/hydromas:
www.dogleggs.com 1-800-313-1218
Dog and Cat Wheelchairs // Rehabilitation Carts
www.eddieswheels.com 1-888-211-2700 Eddie's Wheels
www.doggon.com 1-888-736-4466 Doggon' Wheels
www.k9carts.com 1-800-578-6960 K-9 Carts
Thanks for Your Support!
This page was last edited 06/21/04
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This page is authored by
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copyright ©1996,1997,1998,1999,2000,2001,2002,2003,2004- TierCom, Inc
This page was last edited 06/21/04
Subscriber homepage |Backissues | Breed index |
Vetinfo | vetinfo4cats| vetinfo4dogs | Canine Encyclopedia |
Feline Encyclopedia| VetInfo Digest |Links |Zoonotic infoPlease do not send anything in attachment form. We will not be able to open it due to security risks.
This page is authored by
Dr Michael Richards, DVM
and produced by TierCom, Inc.
Opinions expressed are those of Dr. Richards.
Designed and edited by Michal Justis
copyright ©1996,1997,1998,1999,2000,2001,2002- TierCom, Inc