Hydromorphone hydrochloride is a pure opioid agonist with the principal therapeutic activity of analgesia. It has an analgesic potency approximately two to eight times greater than that of morphine and has a rapid onset of action. A significant feature of the analgesia is that it can occur without loss of consciousness.
Analgesic (narcotic). Preparation by electrolytic reduction of Morphine.
Controlled substance (opiate).
Narcotic opiate analgesic; μ opioid receptor agonist.
Hydromorphone is a potent μ agonist (eight times greater than morphine) that is used to treat severe pain. It is available in intramuscular, intravenous, subcutaneous, oral, and rectal dosage forms. Like all strong μ agonists, hydromorphone is addicting and is a Schedule II drug. Hydromorphone has an oral:parenteral potency ratio of 5:1. The plasma half-lives after parenteral and oral dosage are 2.5 and 4 hours, respectively.
Poison by
subcutaneous and intravenous routes.
Experimental teratogenic effects. A
powerful analgesic. When heated to
decomposition it emits very toxic fumes of
NOx and HCl. See also MORPHINE.
Potentially hazardous interactions with other drugs
Alcohol: can cause dose dumping with sustained
release preparations.
Analgesics: possible opioid withdrawal effects with
buprenorphine and pentazocine.
Antidepressants: possible CNS excitation or
depression with MAOIs - avoid concomitant use
and for 2 weeks after stopping MAOI; possible
CNS excitation or depression with moclobemide;
increased sedative effects with tricyclics.
Antihistamines: increased sedative effects with
sedating antihistamines.
Antipsychotics: enhanced hypotensive and sedative
effects.
Dopaminergics: avoid with selegiline.
Nalmefene: avoid concomitant use.
Sodium oxybate: enhanced effect of sodium oxybate
- avoid.
Hydromorphone undergoes extensive firstpass
metabolism. It is extensively metabolised
by glucuronidation in the liver and excreted in
the urine mainly as conjugated hydromorphone,
dihydroisomorphine, and dihydromorphine.
