Interindividual Variability of the Clinical Pharmacokinetics of Methadone

@article{Eap2002InterindividualVO,
  title={Interindividual Variability of the Clinical Pharmacokinetics of Methadone},
  author={Chin B. Eap and Thierry Buclin and Pierre Baumann},
  journal={Clinical Pharmacokinetics},
  year={2002},
  volume={41},
  pages={1153-1193}
}
Methadone is widely used for the treatment of opioid dependence. Although in most countries the drug is administered as a racemic mixture of (R)- and (S)-methadone, (R)-methadone accounts for most, if not all, of the opioid effects. Methadone can be detected in the blood 15–45 minutes after oral administration, with peak plasma concentration at 2.5–4 hours. Methadone has a mean bioavailability of around 75% (range 36–100%). Methadone is highly bound to plasma proteins, in particular to α1-acid… 
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TLDR
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