From Dog

Alfaxolone (alfaxalone-2-hydroxypropyl-beta-cyclodextrin) is an intravenous anesthetic agents used to induce sedation or general anesthesia[1].

This drug can be used alone, or as an induction agent prior to gaseous anesthesia with drugs such as isoflurane or halothane[2].

It has no analgesic properties and is therefore inferior to drugs such as thiopentone, diazepam/fentanyl[3] and propofol[4].

Duration of action is variable but commonly last for 15 - 20 minutes. Top-up doses can be used to lengthen duration of anesthesia.

The administration of alfaxalone results in dose-dependent tachycardia followed by bradycardia[5], biphasic EEG changes[6] and respiratory depression[7].

This drug can safely be used on dogs under 12 weeks of age[8] and in geriatric patients.

Premedication with atropine, buprenorphine, medetomidine[9] and acepromazine or methadone is recommended[10].

Recommended dose rate is 1.5 - 4.0 mg/kg body weight, given intravenously[11].


  1. Ambros B et al (2008) Comparison of the anesthetic efficacy and cardiopulmonary effects of continuous rate infusions of alfaxalone-2-hydroxypropyl-beta-cyclodextrin and propofol in dogs. Am J Vet Res 69(11):1391-1398
  2. Herbert GL et al (2013) Alfaxalone for total intravenous anaesthesia in dogs undergoing ovariohysterectomy: a comparison of premedication with acepromazine or dexmedetomidine. Vet Anaesth Analg 40(2):124-133
  3. Psatha E et al (2011) Clinical efficacy and cardiorespiratory effects of alfaxalone, or diazepam/fentanyl for induction of anaesthesia in dogs that are a poor anaesthetic risk. Vet Anaesth Analg 38(1):24-36
  4. Michou JN et al (2012) Comparison of pain on injection during induction of anaesthesia with alfaxalone and two formulations of propofol in dogs. Vet Anaesth Analg 39(3):275-281
  5. Muir W et al (2008) Cardiorespiratory and anesthetic effects of clinical and supraclinical doses of alfaxalone in dogs. Vet Anaesth Analg 35(6):451-462
  6. Ambrisko TD et al (2011) Effect of alfaxalone infusion on the electroencephalogram of dogs anaesthetized with halothane. Vet Anaesth Analg 38(6):529-535
  7. Keates H & Whittem T (2012) Effect of intravenous dose escalation with alfaxalone and propofol on occurrence of apnoea in the dog. Res Vet Sci 93(2):904-906
  8. O'Hagan B et al (2012) Clinical evaluation of alfaxalone as an anaesthetic induction agent in dogs less than 12 weeks of age. Aust Vet J 90(9):346-350
  9. Maddern K et al (2010) Alfaxalone induction dose following administration of medetomidine and butorphanol in the dog. Vet Anaesth Analg 37(1):7-13
  10. Jiménez CP et al (2012) Evaluation of the quality of the recovery after administration of propofol or alfaxalone for induction of anaesthesia in dogs anaesthetized for magnetic resonance imaging. Vet Anaesth Analg 39(2):151-159
  11. Rodríguez JM et al (2012) Comparison of the cardiopulmonary parameters after induction of anaesthesia with alphaxalone or etomidate in dogs. Vet Anaesth Analg 39(4):357-365