Table 2.

Drug interactions and toxicity of antimicrobials with methadone and buprenorphine22

Antimicrobial agentPotential toxicityRecommendation
Fluoroquinolones (eg ciprofloxacin, levofloxacin or moxifloxacin)

  • Increasing concentration of methadone

  • Prolongation of QT interval (methadone)

Avoid
Macrolides (eg clarithromycin or erythromycin)

  • Increasing concentration of methadone or buprenorphine

  • Prolongation of QT interval (methadone)

Avoid
Oxazolidinones (eg linezolid)

  • Increasing risk of serotonin syndrome (methadone)

Avoid
Rifampicin

  • Decreasing concentration of methadone or buprenorphine

Monitor and increase dose of methadone or buprenorphine while on rifampicin then decrease at the end of the course
Antiretrovirals (eg efavirenz, nevirapine, abacavir or some protease inhibitors)

  • Increasing/decreasing concentration of methadone or buprenorphine

Consult Liverpool HIV Drug Interactions checker
Direct agents against hepatitis B and C (eg some NS5A inhibitors)

  • Increasing concentration of buprenorphine

Avoid
Antifungals (eg amphotericin B or fluconazole)

  • Increasing risk of hypokalaemia and torsade de pointes (methadone)

  • Fluconazole increases concentration of methadone or buprenorphine

Avoid
Antimalarials (eg arthemether, mefloquine or quinine)

  • Prolongation of QT interval (methadone)

Avoid
Antiprotozoal (eg pentamidine)

  • Prolongation of QT interval (methadone)

Avoid
Antimycobacterial (eg bedaquiline or delamanid)

  • Prolongation of QT interval (methadone)

Avoid