I assume its to calm down animals or to stop seizes

Quote:

Diazepam For Veterinary Use
by Barbara Forney, VMD

Diazepam is a benzodiazepine tranquilizer. Drugs in this class act directly on the brain and are central nervous system (CNS) depressants. Although the precise mechanism of action is not fully known, specific benzodiazepine receptors have been found in the brain and other tissues including the heart, kidney, liver and lungs. Diazepam is used clinically for sedation, to diminish anxiety or modify behavior, as a muscle relaxant, an anticonvulsant, and in some species as an appetite stimulant. It may be administered intra-venously, intra-muscularly, orally and rectally via suppository or enema. Diazepam is metabolized by the liver to nordiazepam and other active metabolites. They are excreted in the urine.

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