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.
