Ø Hypericin and Hyperforin found to be the active ingredients of St. John’s wort.
Ø SJW can interact significantly with certain drugs including…
§ Warfarin
§ Cyclosporine
§ Oral contraceptives
§ Theophylline
§ Digoxin
§ HIV protease inhibitors
§ Selective Serotonin Re-uptake Inhibitors (SSRIs)
§ CYP1A2 Substrates
§ CYP3A4 Substrates
§ CYP2C19 Substrates
§ CYP2C9 Substrates
Ø The risk of clotting might be elevated by the concomitant use of SJW and Warfarin.
Ø Rejection of a transplanted organ may occur due to the interaction of SJW with Cyclosporine (Immunosuppressant).
Ø Treatment failure and drug resistance are expected to occur with Protease Inhibitors such as Indinavir, Amprenavir, Nelfinavir, Ritonavir and Saquinavir due to the inclusion of SJW.
Ø Oral contraceptives may lose their efficacy when they are administered with SJW.
Ø The effectiveness of Digoxin might be reduced by the coadministration of SJW.
Ø Concomitant use of SJW and Theophylline may result into decreased effectiveness of Theophylline.
Ø SJW interact pharmacodynamically with Selective Serotonin Reuptake Inhibitors (SSRIs) and increase the risk of Serotonin syndrome.
Ø Hyperforin of SJW is an inducer of CYP3A4 and hence it can decrease the effectiveness of CYP3A4 Substrates like Alprazolam, Imatinib, Irinotecan, Tacrolimus, etc.
Ø Hypericin of SJW is an inducer of CYP1A2 and hence it can decrease the effectiveness of CYP1A2 substrates such as Theophylline, Warfarin, Paracetamol, Verapamil, etc.
Ø The efficacy of CYP2C19 Substrates like Phenytoin, Phenobarbital, Mephenytoin, etc. might be decreased by SJW.
Ø SJW is also an inducer of CYP2C9 and it can reduce the efficacy of CYP2C9 Substrates such as Phenytoin, Sulfonylureas, NSAIDs, etc.
Ø The patients should consult their doctor or pharmacist to know about the safety of a supplement or herb.
