Tendon versus Ligament

While people tend to think sedatives & tranquilizers are indistinguishable, they are actually very different and have disparate effects on our horses.


Here are some notable differences between the two drug types:

  • While they both produce a calming effect, sedatives offer increased analgesia or pain relief as compared to tranquilizers.

  • While under sedation, most horses are relatively unaware of their surroundings. A tranquilized horse is generally aware of its surroundings although doesn't appear to care.

  • Sedatives are generally used by veterinarians desiring to suppress brain activity and overall awareness in an attempt to prevent movement (such as during a standing surgical procedure). Tranquilizers, on the other hand, are used to reduce anxiety during some form of activity (such as breeding or loading onto a trailer).

  • Since horses are generally not going to remember or learn anything while under sedation, they are typically not asked to "do" anything except stand still. In contrast, tranquilization often helps horses to perform/ learn tasks while reducing any associated anxiety(ies).


What is a SEDATIVE?

Sedatives include a variety of drugs, all of which work by depressing the central nervous system. Xylazine (Rompun®), Detomidine (Dormosedan®), Diazepam (Valium®), Barbiturates and benzodiazepines are the most common forms used in equine veterinary medicine.

Sedatives, also known as depressants, slow both mentation and body functions. Alcohol produces sedation in humans.



Tranquilizers are central nervous system-depressant drugs classified as sedative-hypnotics. Tranquilizers are classified into two main categories:

  • Minor tranquilizers (anxiolytics, or anti-anxiety agents). Minor tranquilizers are used in the treatment of anxiety, tension, panic attacks, and insomnia in humans.

  • Major tranquilizers (neuroleptics). These drugs are used to treat severe mental illness in people.

Tranquilizers impair nerve communication between brain and body. Acepromazine, reserpine and ketamine are common tranquilizers used in horses.


It should be noted that recommended doses will typically achieve optimum results. Higher (unwarranted) doses may only serve to increase the amount of negative side effects associated with a particular drug.  Remember all drugs have negative side effects, and some may even seem to go against prescribed indications.


The Atlanta Equine Clinic - 2014
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