Methadone is a naturally long-acting analgesic with unique pharmacodynamic and pharmacokinetic properties compared to other opioids, available now in India, to treat severe pain. It has the potential to dramatically relieve suffering among patients with serious illness who are living with persistent physical pain. However, clinicians must appreciate its unique pharmacologic properties and its use in clinical practice safely and effectively. The available formulation in India is a racemic mixture of the S- and R-enantiomers, and as such, it will have a propensity for drug-drug and drug-genetic interactions that can increase the risk of Torsades de Point and respiratory depression. Appropriate patient selection, careful dosing and thorough monitoring of methadone will mitigate these risks.
Keywords: Drug interactions; India; methadone; pharmacology.