How are Animals Tranquilized?
In veterinary medicine, sedatives and tranquilizers are commonly used in animals to produce calmness, for chemical restraint, and as an adjunct to general anesthesia.1 In general, tranquilization reduces anxiety and induces a sense of tranquility without drowsiness, while sedation has a stronger effect and produces drowsiness and hypnosis. That said, there can be some overlap in the drug classes and types that are used to produce both tranquilization and sedation. Drugs that produce tranquilization and sedation have different mechanisms of actions, physiological effects, pharmacodynamics, levels of analgesia and reversibility.2
Veterinary Tranquilizers and Sedatives
Phenothiazines
Phenothiazines (or neuroleptics) were originally developed and used as antipsychotic drugs for the treatment of schizophrenia in humans, but these have been used in veterinary medicine as tranquilizers for over 50 years.1Acepromazine is the most widely used phenothiazine derivative in veterinary medicine. While it is only FDA-approved for use in dogs, cats, and horses in the U.S., it is routinely used off-label for sedation of many veterinary species.
Benzodiazepines
Benzodiazepines are classified as sedative/hypnotics due to their ability to cause light sedation and sleep.1 They are used in veterinary medicine as anticonvulsants, adjuncts to anesthetic induction agents, muscle relaxants and for behavioral modification. In healthy animals, behavioral effects are mild. Diazepam, midazolam, lorazepam and zolazepam are examples of benzodiazepines.
Alpha-2-Adrenergic Receptor Agonists (α-2 Adrenergic Agonists)
Alpha-2-adrenergic agonist drugs are very widely used in veterinary medicine due to their ability to produce significant, reliable sedation as well as analgesia. These drugs also act synergistically with opioids. Alpha-2-adrenergic agonists can be reversed with the use of α2-adrenergic antagonists.2 Xylazine is the most widely used α-2 adrenergic agonist in veterinary medicine. Other drugs in this class include detomidine, romifidine, medetomidine and dexmedetomidine.
Routes of Administration
Depending upon the class of drug used, venue and requirements, the administration of tranquilizing and/or sedative drugs may be oral, intravenous or intramuscular.2 In the traditional veterinary clinic treating domestic species, this is generally a straightforward proposition. While hand injection is the most direct method of tranquilizing/sedative agents to an animal, this becomes a necessity in the case of many unrestrained nondomestic species. For exotic species, injectable agents are usually used; in the zoo setting, this may be accomplished via a pole syringe. For potentially dangerous animals and those in the field, remote delivery systems consisting of a dart and projector are the most practical options.
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2Nielsen, L. Chemical Immobilization of Wild and Exotic Animals. (1999) Ames, Iowa, Iowa State University Press.
About NexGen Pharmaceuticals
NexGen Pharmaceuticals is an industry-leading veterinary compounding pharmacy, offering sterile and non-sterile compounding services nationwide. Unlike other veterinary compounding pharmacies, NexGen focuses on drugs that are difficult to find or are no longer available due to manufacturer discontinuance or have yet to be offered commercially for veterinary applications, but which still serve a critical need for our customers. We also specialize in wildlife pharmaceuticals, including sedatives and their antagonists, offering many unique options to serve a wide array of zoo animal and wildlife immobilization and anesthesia requirements.
Our pharmacists are also encouraged to develop strong working relationships with our veterinarians in order to better care for veterinary patients. Such relationships foster an ever-increasing knowledge base upon which pharmacists and veterinarians can draw, making both significantly more effective in their professional roles.
Disclaimer
The information contained in this blog post is general in nature and is intended for use as an informational aid. It does not cover all possible uses, actions, precautions, side effects, or interactions of the medications shown, nor is the information intended as medical advice or diagnosis for individual health problems or for making an evaluation as to the risks and benefits of using a particular medication. You should consult your veterinarian about diagnosis and treatment of any health problems. Information and statements have not been evaluated by the Food and Drug Administration ("FDA"), nor has the FDA approved the medications to diagnose, cure or prevent disease. Medications compounded by NexGen Pharmaceuticals are prepared at the direction of a veterinarian. NexGen Pharmaceuticals compounded veterinary preparations are not intended for use in food and food-producing animals.
NexGen Pharmaceuticals, LLC does not recommend, endorse or make any representation about the efficacy, appropriateness or suitability of any specific dosing, products, procedures, treatments, services, opinions, veterinary care providers or other information that may be contained in this blog post. NEXGEN PHARMACEUTICALS, LLC IS NOT RESPONSIBLE NOR LIABLE FOR ANY ADVICE, COURSE OF TREATMENT, DIAGNOSIS OR ANY OTHER INFORMATION, SERVICES OR PRODUCTS THAT YOU OBTAIN THROUGH THIS BLOG POST.