This information describes the common uses of St. John’s Wort, how it works, and its possible side effects.
Tell your healthcare providers about any dietary supplements you’re taking, such as herbs, vitamins, minerals, and natural or home remedies. This will help them manage your care and keep you safe.
What is it?
St. John’s wort is an herb with yellow flowers used in traditional European medicine. St. John’s wort supplements come as tablets, capsules, liquid extracts, and creams.
What are the potential uses and benefits?
St. John’s wort is used to:
- Treat mild and moderate depression
- Treat anxiety
- Manage fatigue (feeling very tired or having less energy than usual)
- Treat insomnia (trouble falling asleep, staying asleep, or waking up too early)
- Manage symptoms caused by menopause (the permanent end of your menstrual cycles), such as hot flashes
- Treat seasonal affective disorder (SAD)
- Treat attention-deficit hyperactivity disorder (ADHD — a condition that can cause unusual levels of hyperactivity and impulsive behaviors)
- Heal wounds
St. John’s wort has other uses, but doctors haven’t studied them to see if they work.
Talk with your healthcare provider before taking St. John’s wort supplements. Herbal supplements can interact with some medications and affect how they work. For more information, read the “What else do I need to know?” section below.
What are the side effects?
Side effects of using St. John’s wort may include:
- Headache
- Nausea (feeling like you’re going to throw up)
- Dry mouth
- Abdominal (belly) discomfort
- Sleepiness
- Increased sensitivity to sunlight
What else do I need to know?
- Talk with your healthcare provider if you are:
- Taking a blood thinner, such as warfarin (Coumadin®, Jantoven®). St. John’s wort can affect the way it works.
- Taking a cholesterol-lowering medication, such as simvastatin (FloLipid®, Zocor®). St. John’s wort can make it less effective.
- Taking a heart medication, such as digoxin (Digox®, Lanoxin®). St. John’s wort makes it less effective.
- Taking antidepressants, such as fluoxetine (Prozac®) or paroxetine (Paxil®). St. John’s wort can make them less effective.
- Taking a birth control pill. St. John’s wort can affect the way the pill works in your body.
- An organ transplant patient and are taking cyclosporine (Sandimmune®, Neoral®) or tacrolimus (Prograf®). St. John’s wort can make these medications less effective. This can make your body reject the transplant.
- Taking the chemotherapy medications irinotecan (Onivyde®, Camptosar®) or imatinib (Gleevec®). St. John’s wort can make these less effective.
- Taking indinavir (Crixivan®) to treat HIV (human immunodeficiency virus) infection. St. John’s wort makes it less effective by reducing its level in your blood.
- Don’t take St. John’s wort if you’re pregnant or breastfeeding. It may not be safe for you.