St. John's Wort - Topic Overview
What is St. John's wort?
St. John's wort (Hypericum perforatum) is a plant with yellow flowers that
people in European countries have used for centuries to treat mild to moderate
depression. In the United States, it is sold as a
dietary supplement and can be found at health food stores and pharmacies.
What is St. John's wort used for?
St. John's wort
is used in the short-term treatment of mild to moderate depression.
It may take up to 2
to 3 weeks for St. John's wort to improve depressive symptoms. Not all
preparations of St. John's wort are the same. A standardized form means the
amount of St. John's wort is the same in every capsule.
Is St. John's wort safe?
St. John's wort causes
fewer side effects (such as digestive discomfort or headaches) than
antidepressant medicines, although it may cause a rash with sun
St. John's wort may interact with medicines used to
treat some other illnesses, such as
AIDS. It is important to let your doctor or pharmacist
know if you want to try St. John's wort so that he or she can determine whether
it might interfere with other medicines you are taking.
- Do not take St. John's
wort while you are taking other antidepressants. You may overmedicate yourself,
resulting in serious negative side effects. Always talk with your doctor before
you take any herbal remedies to treat depression or other
- Do not take St. John's wort
while you are taking protease inhibitors (PIs) or nucleoside reverse
transcriptase inhibitors (NRTIs) for the treatment of
- Do not take St. John's wort while you are pregnant or
The U.S. Food and Drug Administration (FDA) does not
regulate dietary supplements in the same way it regulates medicines. A dietary
supplement can be sold with limited or no research on how well it works.
Always tell your doctor if you are using a dietary supplement or
if you are thinking about combining a dietary supplement with your conventional
medical treatment. It may not be safe to forgo your conventional medical
treatment and rely only on a dietary supplement. This is especially important
for women who are pregnant or breast-feeding.
When using dietary
supplements, keep in mind the following:
- Like conventional medicines, dietary
supplements may cause side effects, trigger allergic reactions, or interact
with prescription and nonprescription medicines or other supplements you are
taking. A side effect or interaction with another medicine or supplement may
make other health conditions worse.
- Dietary supplements may not
be standardized in their manufacturing. This means that how well they work or
any side effects they cause may differ among brands or even within different
lots of the same brand. The form you buy in health food or grocery stores may
not be the same as the form used in research.
- The long-term
effects of most dietary supplements, other than vitamins and minerals, are not
known. Many dietary supplements are not used long-term.