From Dog

Hydromorphone, the active metabolite of hydrocodone[1], is an analgesic and pre-anesthetic agent[2].

Unlike many pre-anesthetic and anesthetic agents which result in splenic enlargement, hydromorphone usually results in reduced splenic volume[3].

Side-effects such as vomiting can be mitigated by pre-administration of maropitant[4].

Recommended dose rate in dogs is 0.05 - 0.1 mg/kg given intramuscularly or subcutaneously every 24 hours.


  1. Kukanich B & Spade J (2012) Pharmacokinetics of hydrocodone and hydromorphone after oral hydrocodone in healthy Greyhound dogs. Vet J Oct 22
  2. Posner LP et al (2013) Apheresis in three dogs weighing <14 kg. Vet Anaesth Analg Mar 1
  3. Baldo CF et al (2012) Effects of anesthetic drugs on canine splenic volume determined via computed tomography. Am J Vet Res 73(11):1715-1719
  4. Hay Kraus BL (2013) Efficacy of maropitant in preventing vomiting in dogs premedicated with hydromorphone. Vet Anaesth Analg 40(1):28-34