Methadone Monoamine oxidase inhibitors

In patients with reduced respiratory reserve, such as those with emphysema, severe obesity, cor pulmonale, and kyphoscoliosis, opioids must be used with caution. The relative benefits and harms of using opioids in patients taking monoamine oxidase inhibitors, those with a history of drug abuse, asthma, hepatic impairment, hypotension, raised intracranial pressure, or head injury, and during pregnancy or breast feeding, should be carefully considered. Dextropropoxyphene, pethidine, and methadone should be used with caution (SEDA-21, 85). 

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