Oxymorphone injectable

Robinson et al. [8] noted that oxymorphone injectable was less likely to release histamine in dogs than equivalent doses of morphine. Since cardiovascular effects associated with histamine release (vasodilatation, hypotension) are minimal with oxymorphone this opioid may offer safety advantages for patients presenting with cardio- and cerebrovascular disease. 

Oxymorphone is available for oral, rectal, and parenteral administration. Oxymorphone injectable (OPANA Injection ) is available in 1 mL ampoules containing 1 mg/mL oxymorphone hydrochloride. In addition, each 1 mg/mL ampule contains 8.0 mg/mL sodium chloride. pH is adjusted with hydrochloric acid. 

Nalbuphine hydrochloride is structurally related to oxymorphone and naloxone. It is approximately equipotent with morphine. Nalbuphine is metabolised in the liver to inactive metabolites. The plasma terminal half-life is approximately 5 h. The onset of analgesia is within 2-3 min of intravenous administration and 15 min after intramuscular injection, and lasts 3-6 h with an adult dose of 10 mg. With equi-analgesic doses, similar degrees of respiratory depression to that of morphine occur up to a dose of approximately 0.45 mg-kg-1. With higher doses a ceiling effect occurs. Sedation, possibly mediated by K-receptor activation, occasionally occurs. The incidence of psychotomimetic side effects is lower than with pentazocine. The abuse potential is low, but is can cause withdrawal symptoms in opioid-dependent subjects. It has occasionally been used to reverse opioid-induced respiratory depression. 

Urticaria at the site of injection is due to histamine release. It is seen with pethidine and morphine, but not with oxymorphone, methadone, fentanyl, or sufentanil. Wheal and flare responses to various opioids differ (41). 

Hydromorphone is more potent, has better oral absorption characteristics, and is more soluble than morphine, but its overall pharmacologic profile parallels that of morphine. A sustained-release hydromorphone product has recently become available. Oxymorphone can be administered rectally and by injection. Although it is more potent than morphine, it offers no real pharmacologic advantages. Levor-phanol has an extended half-life, bnt its overall therapeutic effects are similar to those of morphine. 

OXYMORPHONE HYDROCHLORIDE (Numorphan injection 1 mg/mL, injection 1.5 mg/mL, suppositories 5 mg)... 

Therapeutic doses of morphine cause dilation of cutaneous blood vessels. The skin of the face, neck, and upper thorax frequently becomes flushed. These changes may be due in part to the release of histamine and may be responsible for the sweating and pruritus that occasionally follow the systemic administration of morphine. Histamine release probably accounts for the urticaria commonly seen at the site of injection, which is not mediated by opioid receptors and is not blocked by naloxone. It is seen with morphine and meperidine but not with oxymorphone, methadone, fentanyl, or sufentanil. 

It is not known whether oxymorphone is excreted in human milk. Because many drugs, including some opioids, are excreted in human milk, caution should be exercised when OPANA injection is administered to a nursing woman. Ordinarily, nursing should not be undertaken while a patient is receiving oxymor-... 

Injectable oxymorphone is not associated with CYP450 PK drug-drug interactions at clinically relevant doses. No dose adjustments required for concomitant medications metabolized via the CYP450 pathway. 

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