St. John's Wort - Aspirin, Codeine Phosphate, Phenobarbital Interaction

Interaction Details

Aspirin, Codeine Phosphate, Phenobarbital is classified as belonging to the following category: Phenobarbital (Luminal)

St. John's wort decreases the levels and clinical effects of phenobarbital.
St. John's wort may increase the metabolism of phenobarbital. Plasma concentrations of phenobarbital should be monitored carefully. The dose of phenobarbital may need to be increased when St. John's wort is started and decreased when it is stopped.

Interaction Rating

Likelihood of Occurrence

Well-controlled human studies have demonstrated the likely existence of this interaction

References

• Henderson L, Yue QY, Bergquist C, et al. St John's wort (Hypericum perforatum): drug interactions and clinical outcomes. Br J Clin Pharmacol 2002;54:349-56..

Interaction Details

Aspirin, Codeine Phosphate, Phenobarbital is classified as belonging to the following category: Cytochrome P450 2B6 (Cyp2B6) Substrates

St. John's wort may increase the metabolism and reduce the levels of CYP2B6 substrates.
Clinical research shows that taking St. John's wort 325 mg three times daily for 14 days along with bupropion, a CYP2B6 substrate, reduces the area under the concentration-time curve by approximately 14% and increases the clearance of bupropion by approximately 20%.

Interaction Rating

Likelihood of Occurrence

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists

References

• Lei HP, Yu XY, Xie HT, et al. Effect of St. John's wort supplementation on the pharmacokinetics of bupropion in healthy male Chinese volunteers. Xenobiotica 2010;40(4):275-81.

St. John's Wort - More Interactions

St. John's Wort interacts with 1115 drugs

Interaction Rating Key

These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.