I remembered an earlier topic a while back about Acepromazine related to fearful dogs and air transport so I PM'd Red for her advice about Ace prior to my Molly's surgery as the vet had run through the list of drugs she would have to take post-op during our consult. Since Red's description of what the drug does is so clear, I have quoted it here:
Red wrote:Yes, it was probably me who said something about Acepromazine because it is prescribed for fearful dogs when it should be a big no no.It is basically a dopamine antagonist that decreases locomotor responsiveness and therefore both abnormal and normal behavior. It does not affect emotions in a productive manner and that is why it should not be used for prior a flight ( it has an effect on body thermoregulation as well), vet procedures or any other situations in which stress and fear are present. Pretty much you have a dog who cannot move but is still capable to experience emotions.Imagine a fearful dog in a situation that frighten him, can hear and smell, but cannot fully react to the environment. On top of that there are possible side effects such as increased noise sensitivity, muscle spasms, body temperature and more.
That said, ACE can be used on easy going dogs who don't have a care in the world, for a short amount of time.
A few nights ago, I gave Molly a full pill of Ace about 45 minutes before we were supposed to go out to dinner at a friend's house. The previous two nights, I had given Molly half pills of Ace to help her sleep through the night. The Acepromazine was prescribed by my vet as an anti-anxiety medication to help her recover from surgery and to soften the effects of the Tramadol pain reliever that was also prescribed. When we were ready to leave, Molly became extremely stressed (heavy, rapid panting and whining) so I told my BF to go and I would join him later when I felt like Molly had sufficiently calmed down. It took another hour for her to calm down, but even then I could tell she was still stressed. She was panting less and lying on her side but her eyes were completely bloodshot.
I decided to stay home that night so I could monitor any other reactions. Nothing else happened – Molly's reactions were really mild but after reading about the dramatic effects described in a thread from another forum member (see paragraph 6 of OP and subsequent thread comments towards the end of page 1: viewtopic.php?f=2&t=129990), I'm glad I stayed home to keep watch on her.