Name: Xylazine

Trade Name(s): Rompun, Anased, Xylazine HCl Injection

Preparation: Sterile injectable liquid packaged in 20 ml vials with a concentration of 20 mg/ml, or 50 ml vials with a concentration of 100 mg/ml.

Description: Xylazine is an alpha-2-adrenergic agonist sedative with analgesic properties.

Availability: Xylazine is a prescription drug.

Indications: Used alone for short minor manipulations or minor surgical procedures.  See below for use in combination with other drugs for anesthesia.

Dosage: Consult the laboratory animal veterinarian.

Routes of administration: Intramuscular, subcutaneous, or intravenous

Duration of action: Sedation lasts a few hours; the analgesia is of shorter duration.  ROMPUN is a potent sedative and analgesic as well as a muscle relaxant. Its sedative and analgesic activity is related to central nervous system depression. Its muscle-relaxant effect is based on inhibition of the intraneural transmission of impulses In the central nervous system.  Sedation develops within 10-15 minutes after intramuscular injection and within 3-5 minutes following intravenous administration.

Mechanism of analgesic action: Xylazine is an alpha-2-adrenergic agonist sedative with analgesic properties.  Its sedative properties relate to central nervous system depression.  The muscle ­relaxant properties relate to inhibition of the Intraneural transmission of Impulses In the central nervous system.

Clinical pharmacology: The sedation and muscle relaxation produce a sleep-like state, with decreased respiratory and heart rates.  There is significant depression of respiration and heart rate.  The decrease in heart rate is related to a transient change in conductivity of cardiac muscle due to a partial atrioventricular block.

Physiological effects:

         Cardiovascular: Significant depession of heart rate

         Respiratory: Significant respiratory depression

Drug Interactions: Should not be used in combination with other tranquilisers.  There are additive effects when used in combination with anesthetics or analgesics and then required doses would be lower.

Notes: In dogs and cats vomiting may occur soon after administration of xylazine.


Compendium of Veterinary Products, 6th Ed.  1999.  Canadian Animal Health Institute. North American Compendiums, Hensall, Ontario

Pain Management in Animals.  2000  Flecknell P and Waterman-Pearson A (eds). WB Saunders, London  184pp

Laboratory Animal Anesthesia.  1996.  Flecknell P.  Academic Press, London.  274 pp.