How the interaction occurs:
St. John's wort may increase how quickly your body processes digoxin.
What might happen:
Your digoxin levels may decrease, which may decrease the effectiveness of your digoxin.
What you should do about this interaction:
Make sure that your healthcare professionals (e.g. doctor or pharmacist) know that you are taking St. John's wort. Your doctor may want to check your blood level of digoxin and adjust the dose of your medicine. If you experience shortness of breath or a fast heartbeat, contact your doctor.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.
1.Johne A, Brockmoller J, Bauer S, Maurer A, Langheinrich M, Roots I. Pharmacokinetic interaction of digoxin with an herbal extract from St John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999 Oct; 66(4):338-45.
2.Lanoxin (digoxin) Tablets US prescribing information. GlaxoSmithKline August, 2012.