Medication - Acepromazine

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Sedative Questions - PromAce Rx

Q: What do you believe to be the fastest acting sedative for a dog? The safest to use? The one with the least side effects? Given orally, SC or IM? (For the purposes of seperation anxiety, dental care for a dog whose teeth are   in good condition, but is too anxious to allow it's teeth and gums to be cleaned and scaled without being sedated), and, is there a sedative (not general anesthesia) you would avoid using completely on sensitive breeds & sight hounds?  

A: I only use one sedative on a regular basis, acetylpromazine (PromAce Rx). I do not know if it is the fastest acting, or not, but when given IV it acts pretty quickly and when given subcutaneously it takes about fifteen minutes for a dog to exhibit signs of sedation. We use this mostly as a pre-operative medication and occasionally for car sickness (orally).

Sedatives are not very helpful for separation anxiety, based on our clinical experiences. We have better luck with selective seritonin re-uptake inhibitiors (SSRIs) like fluoxetine (Prozac Rx) or clomipramine (Clomicalm Rx) or tri-cyclic antidepressants like amitriptyline. I won't administer sedatives or dispense them for use in pets for grooming or teeth cleaning purposes because the effect is unreliable and unpredictable and I do not want anyone counting on them working and getting hurt. Sometimes, I will use a combination of a sedative like acetylpromazine and a narcotic pain reliever like oxymorphone or butophanol for use in combination with local anesthesia for minor surgical procedures, which seems to be a little more reliable combination.

Mike Richards, DVM 

Acepromazine

Acepromazine is one of the most commonly used tranquilizers in veterinary medicine. It is a phenothiazine compound. Its mode of action is only partially understood but it involves blockage of dopamine nerve receptors in the brain. It causes tranquilization and also has an anti-emetic effect. This makes it especially useful for treating car sickness, since that is often a combination of fear and motion sickness in dogs.

The recommended dosage for acepromazine is 0.25mg to 1mg per pound of body weight. In most cases it is not necessary to use the higher dosages. That is not true for use in trying to control fear based aggression. Acepromazine is considered to be very safe. The average toxic dose is significantly higher than the recommended dosage (at least 20 times the dose). Despite this, acepromazine does have some significant effects that must be considered. It can cause hypotension (lowering of blood pressure). This effect may be exaggerated in Boxers and there have been anecdotal reports of death of Boxers after the use of acepromazine. In addition, acepromazine seems to make it easier for dogs with seizure disorders to have a seizure. This medication should not be used near the time of dipping or treatment with organophosphates for flea control.

Acepromazine doesn't have any pain-killing effects. Many dogs seem to be able to will themselves to overcome its effects, at least temporarily. This makes it less than ideal as a drug for dealing with aggressive or fearful dogs but there have not been better alternatives for medicating prior to the visit. It works often enough that many vets will try this approach first. We do this when we think it has a chance of helping make an office visit go easier. We just remember to continue to be very careful when examining the dog.

Mike Richards, DVM  

Acepromazine for Aggression

Q: I have a 2 year old male boxer/pitbull, neutered, approx 70 lbs, not a social dog. Last year the vet prescribed 1 acepromazine, 25 mg, every half hour, beginning 1 1/2 hr before annual visit. My dog was also under the care of a trainer for fear aggression. At the time of the visit, my dog was muzzled, can only be examined from the rear and had a rapid heartbeat, even after being given the recommended dosage.

For this year's visit, I called the vet and asked about medication for this visit. The dog will again have to be muzzled for the visit, he is still not a very social dog. He reveiwed his records and gave acepromazine again, but to give him 3 25mg tablets 2 hrs. prior to visit. I know this drug is classified as a major transquiler, but it seemed to have no effect last year. I like my vet but I am uncomfortable with this advise, perhaps needlessly.

I have tried to locate a Veterinary Pharmaceuticals and Biologicals or the Merck Manual to find out more about this drug, to no avail.

ANY information about this drug or a direction as to find more about this drug would go along way to ease my mind.

Thanking you in advance.

A: Acepromazine is one of the most commonly used tranquilizers in veterinary medicine. It is a phenothiazine compound. Its mode of action is only partially understood but it involves blockage of dopamine nerve receptors in the brain. It causes tranquilization and also has an anti-emetic effect. This makes it especially useful for treating car sickness, since that is often a combination of fear and motion sickness in dogs.

The recommended dosage for acepromazine is 0.25mg to 1mg per pound of body weight. In most cases it is not necessary to use the higher dosages. That is not true for use in trying to control fear based aggression. Acepromazine is considered to be very safe. The average toxic dose is significantly higher than the recommended dosage (at least 20 times the dose). Despite this, acepromazine does have some significant effects that must be considered. It can cause hypotension (lowering of blood pressure). This effect may be exaggerated in Boxers and there have been anecdotal reports of death of Boxers after the use of acepromazine. In addition, acepromazine seems to make it easier for dogs with seizure disorders to have a seizure. This medication should not be used near the time of dipping or treatment with organophosphates for flea control.

Acepromazine doesn't have any pain-killing effects. Many dogs seem to be able to will themselves to overcome its effects, at least temporarily. This makes it less than ideal as a drug for dealing with aggressive or fearful dogs but there have not been better alternatives for medicating prior to the visit. It works often enough that many vets will try this approach first. We do this when we think it has a chance of helping make an office visit go easier. We just remember to continue to be very careful when examining the dog.

Another approach is to use faster acting medications after the dog arrives at the hospital. I have heard from several veterinarians that Telazol, an anesthetic agent, works very well to facilitate examination of aggressive dogs. It is supposed to be injected but despite that, it has proponents. Some vets have used it orally by just squirting it into the aggressive animal's mouth. I haven't tried this medication personally. We have used acepromazine and oxymorphone combinations with good effect. The oxymorphone provides pain relief as well as sedation and that seems to relieve some dogs that would fight acepromazine alone. Oxymorphone can be injected in the office after premedication at home with oral acepromazine.

We see some fearful dogs at home instead of the office. For some reason, this works very well with some of these dogs. It definitely isn't a "cure-all" but it can lessen the strain of the whole procedure on everyone when it works.

Some dogs do get better from year to year as they come in our office. After a few visits they seem to adjust to the scariness of the office or just resign themselves to the inevitability of the visit. Sedation in the early visits does sometimes seem to help this process. Unfortunately, it doesn't always work this way.

I hope your visit goes better this year, though.

Mike Richards, DVM  

Acepromazine Use For Aggression - Continued

Q: I previously wrote to you about acepromzaine. With the approval of my vet, we decided to do a trial run before my annual visit. We followed the directions: 3 25mg tablets 2 hr before visit. It worked in about 1 hr. My dog could bearly stand, he was so sedated. However, he managed to overcome this when a stanger came to the door(about 1 1/2hr after initial dose):after departing, the dog went into a sedated sleep. No problem, this was great, so I thought. Wrong, when I attempted to muzzle this dog, after waking him up and placing him in a sit/stay; He showed his teeth and snapped, luckly me, I was behind him, else I might need emergency care. You can not imagine how surprised I was. Never had I seen my dog do this. I have been muzzle training him since Dec. and we were up to 10 minutes. Now I know what the expression "Let sleeping dogs lie" means. Since my vet is on vacation for the week and the covering vet recommended I speak with my vet. I am running out of time before this annual visit. Is this a normal reaction to this medication? Any suggestions/input as to what I can do would be appreciated.

A: I can't remember exactly what I said, but I was trying to explain that the reason acepromazine isn't ideal for controlling dogs with aggressive tendencies is that they can overcome the effect -- exactly what you saw. They seem to be able to be alert long enough to respond to perceived threats, then slip back into a sedated state. It does help with some dogs and it is inexpensive and readily available, so we keep on trying it but it is necessary to be very cautious (even more cautious) around a sedated aggressive dog.

This is why a number of veterinarians have gone to injecting these dogs on arrival at the hospital with short term anesthetic agents, since these totally incapacitate the dog. The only problem being that you have to get the injection into the dog in the first place or you have to be adept at oral administration if that route is chosen.

We also have a few clients that just muzzle the dog prior to visiting us. It is surprising how many aggressive dogs will just give up and allow examination once muzzled with an effective muzzle. We like the ones from JAFCO but there are several effective designs.

Nothing works all the time to facilitate safe examination of dogs with aggressive tendencies. It is truly a trial and error situation and the consequences of a failed trial can be devastating to the dog, the vet, the owner, or all three. Whatever you decide to do, please be careful....

Mike Richards, DVM

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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...

 

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