The following serious adverse reactions are described, or described in greater detail, in other sections:
The following adverse reactions associated with the use of meperidine were identified in clinical studies or postmarketing reports. Because some of these reactions were reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
The major hazards of meperidine, as with other opioid analgesics, are respiratory depression and, to a lesser degree, circulatory depression; respiratory arrest, shock, and cardiac arrest have occurred.
The most frequently observed adverse reactions include lightheadedness, dizziness, sedation, nausea, vomiting, and sweating. These effects seem to be more prominent in ambulatory patients and in those who are not experiencing severe pain. In such individuals, lower doses are advisable. Some adverse reactions in ambulatory patients may be alleviated if the patient lies down.
Other adverse reactions include:
Nervous System. Mood changes (e.g. euphoria, dysphoria), weakness, headache, agitation, tremor, involuntary muscle movements (e.g. muscle twitches, myoclonus), severe convulsions, transient hallucinations and disorientation, confusion, delirium, visual disturbances.
Inadvertent injection about a nerve trunk may result in sensory-motor paralysis which is usually, though not always, transitory.
Gastrointestinal. Dry mouth, constipation, biliary tract spasm.Cardiovascular. Flushing of the face, tachycardia, bradycardia, palpitation, hypotension [see Warnings and Precautions (5.17)], syncope, phlebitis following intravenous injection.Genitourinary. Urinary retention.Allergic. Pruritus, urticaria, other skin rashes, wheal and flare over the vein with intravenous injection.Hypersensitivity reactions, anaphylaxis.Histamine release leading to hypotension and/or tachycardia, flushing, sweating, and pruritus.Other. Pain at injection site; local tissue irritation and induration following subcutaneous injection, particularly when repeated; antidiuretic effect.
Serotonin syndrome: Cases of serotonin syndrome, a potentially life-threatening condition, have been reported during concomitant use of opioids with serotonergic drugs.
Adrenal insufficiency: Cases of adrenal insufficiency have been reported with opioid use, more often following greater than one month of use.
Androgen deficiency: Cases of androgen deficiency have occurred with chronic use of opioids [see Clinical Pharmacology (12.2)].
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