St John’s wort (Hypericum perforatum) is native to Europe, Asia and North Africa. Originally used by the Greeks to rid the body of evil spirits, it has been used since the 1500s for depression.
What is it used for?
Depression, anxiety, nerve pain, premenstrual syndrome (PMS). It is thought to exert drug-like activity in neurochemical systems believed implicated in the cause of depression.
How is it used?
The flowering tops and aerial parts of the plant are made into teas, extracts and over-the-counter supplements.
At a glance
Main use: Mild to moderate depression
Evidence: There is evidence that St John’s wort might be helpful in mild-moderate depression.
Interacts with other antidepressants, contraceptives and many other medications.
Talk to your doctor before taking St John’s wort in pregnancy.
Remember to always tell your healthcare provider about all the remedies and medications you’re taking.
There is good evidence from many trials and reviews that it may benefit people with depression. Evidence is stronger for benefit in mild to moderate depression, with some studies finding it can be as effective as some antidepressants for mild to moderate depression.
A review of trials in 2009 suggested St John’s wort might be helpful for people with major depression and be at least as effective standard antidepressants with fewer side effects.
However, ongoing research suggestseffectiveness may have been overplayed and other studies have found no benefit in major depression.
Currently the Royal Australasian and New Zealand College of psychiatrists does not recommend St John’s wort for depression.
Also it’s important to be aware the constituents of St John’s wort extracts differ between manufacturers.
Side-effects and interactions
The most common side effects include gastrointestinal upset, light sensitivity, agitation and skin reactions.
Serious side effects can result from taking St John’s wort together with other antidepressants, as well as other supplements and medications. Medications known to interact with St John’s wort include antidepressants, blood thinning drugs, drugs for irregular heartbeats, HIV medication, cancer drugs, immunosuppressants and triptan migraine drugs. St John’s wort can also reduce the effectiveness of the contraceptive pill and other medications. If you are taking any medication consult your doctor before taking St John’s wort to check for possible interactions.