Nora Apothecary

Ketamine in Schedule III

In August, the US Drug Enforcement Administration placed ketamine in Schedule III under the Controlled Substances Act, which impacts many practicing veterinarians. Under Federal law, all businesses which manufacture or distribute controlled drugs; all health professionals (including veterinarians) entitled to dispense, administer or prescribe them; and all pharmacies entitled to fill prescriptions must register with the DEA. Registrants must comply with a series of regulatory requirements relating to drug security, records accountability, and adherence to standards.

Questions related to the registration process may be directed to DEA’s Office of Diversion Control, Registration Unit. This unit has a toll-free number available 24 hours a day. The number, 800-882-9539, is equipped with a voice mail system that may be used to request:

  • New applications for registration,
  • Renewal applications,
  • Duplicate certificates of registration,
  • DEA order forms, and
  • Changes of address.

Callers may speak with a Registration Assistant during normal business hours (8:30 a.m. to 6:00 p.m. EST).

Ketamine is used in human and veterinary medicine to produce a unique anesthetic state characterized by sedation, immobility, marked analgesia, and amnesia. Since 1992, the DEA has documented more than 568 incidents of the sale and/or use of ketamine (known on the street as “Special K” or “K”) in schools by minors, on college campuses, at night clubs and rave dances, incidents of public intoxication and improper operation of a motor vehicle while under the influence of ketamine, burglaries of veterinary clinics in which ketamine was the sole item targeted, and the sale of ketamine to undercover police. During the same period of time, 207 ketamine abuse related visits to hospital emergency departments were recorded by the Drug Abuse Warning Network.

The pharmacological and behavioral effects of ketamine are similar, but somewhat less intense and shorter in duration, to those of PCP. Low dose intoxication with ketamine results in impaired attention, learning, and memory functions. Higher doses may result in ataxia, dizziness, elevated blood pressure, mental confusion, hyper-excitability, catalepsy, convulsions, delusional dreamlike hallucinations, and psychosis. Long-term use of ketamine is associated with hallucinatory flashbacks and an inability to concentrate. Several case reports suggest that psychological dependence and tolerance develop in humans after long-term use of ketamine. Behavioral and physical dependence have been demonstrated in animals.

Diversion of ketamine pharmaceutical products from practitioners has been the most frequently documented source of the drug, with the primary sources being veterinary clinics. The liquid pharmaceutical product is injected or, more commonly, evaporated and the resultant powder inhaled (snorted). Clandestine manufacture of ketamine has not been encountered. In contrast to that of PCP, the synthesis of ketamine is difficult.

Placing ketamine into Schedule III serves as a means to limit the abuse of the drug while ensuring its continued availability for appropriate use (3).


(1) Journal of the American Veterinary Medicine Association, vol 215, No. 2, July 15, 1999, pp 161-183.
(2) Plumb, Donald C. Veterinary Drug Handbook, 3rd ed. Ames: Iowa State University Press, 1999.
(3) Federal Register, April 9. 1999