Reserpine

Description

Reserpine is an alkaloidal chemical derived from the plant Rauwolfia serpentina, sometimes used for long-term sedation of horses. Reserpine works by blocking the storage of some of the brain's chemical messengers, including a neurotransmitter called norepinephrine.

This drug takes many hours to fully take effect and has subtle sedating effects long after the last dose is given. Although some trainers routinely administer it to nervous or excitable horses, many trainers and veterinarians are against this practice because of side effects and the fact that other ways can be used to achieve the same results with most horses, without giving them a chemical medication that may increase health risks.

Usage

Reserpine is used as a long-acting tranquilizer to subdue excitable or difficult horses and has been used illicitly for the sedation of show horses, for-sale horses, and in other circumstances where a "quieter" horse might be desired. Currently, accurate tests are available that can determine if a horse has been given reserpine.

Dosage and Administration

As long-term tranquilizer

Side Effects

Horses vary greatly in their sensitivity to reserpine. Common side effects include colic, gastrointestinal upset, long-term diarrhea, sweating, depression, droopy eyes, and a dropped penis.

Precautions

Little information has been published on the clinical use of reserpine in horses. Much available information is anecdotal and not backed by research.

Reserpine is not FDA approved for use with horses and is a prescription drug restricted by U. S. federal law to use by or on the lawful written or oral order of a licensed veterinarian.

Reserpine is prohibited in most sanctioned competitions and is a frequent cause of drug violations. The proper regulatory group should be consulted regarding rules and regulations.

Interactions

Reserpine may interact with drugs used for general anesthesia. Accurate records should be kept of its use in case an animal is referred to an equine hospital for care or surgery.

Overdose

Overdose results in increased risk and severity of the above mentioned side effects.

The antidote to reserpine is methamphetamine.