Although clinical trials are ongoing for this increasingly popular herbal supplement, it seems clear that for mild depression, St. John’s wort may be an effective treatment. However, there are also reasons why this herb should may not be appropriate, so you should always talk to your doctor before you try this or any other natural supplement.
Why St. John’s Wort Is Not Advised for Bipolar Disorder Patients
The following reasons are cited as to why St. John’s wort is not recommended for people with bipolar disorder.
Serotonin Syndrome
Serotonin syndrome is a condition can occur after the use of certain serotonergic medications and supplements. Symptoms include dizziness, cognitive difficulty, faintness when standing or walking, unsteadiness when walking, muscle spasms, and a racing heartbeat. People may experience this group of symptoms if they take St. John’s Wort when they are also taking an SSRI such as fluoxetine (Prozac) or SNRI like duloxetine (Cymbalta), or and MAOI. Because St. John’s wort may increase the amount of serotonin available, combining the herb with an SSRI such as Prozac or Paxil is not recommended.
Mania Trigger
It is well known that any antidepressant, when taken without a mood stabilizer, can set off a manic or hypomanic episode. Some people never exhibit mania at all until treated for depression with a triggering drug. Researchers at Harvard Medical School and the University of Michigan have issued warnings regarding St. John’s wort as a possible triggering substance. Published case reports have documented several cases of sudden onset of mania in bipolar patients who were using the herbal supplement.
Drug Interactions
In February of 2000, the US Food and Drug Administration released a Public Health Advisory warning that there was a risk of dangerous interactions between St. John’s wort and certain prescription medications. Researchers found that the use of St. John’s wort significantly reduces the effectiveness of some AIDS medications (indinavir and other antiretroviral agents). Drugs mentioned by name that is used in the treatment of mood disorders were:
The tricyclic antidepressants Tofranil (imipramine), Asendin (amoxapine), and Elavil (amitriptyline); The anti-seizure medication Tegretol (carbamazepine), used as a mood stabilizer; and The cancer medication Tamoxifen, which is being studied as a mood stabilizer.
It would be safer to assume that other drugs related to these would also be in the same category, including other tricyclics such as Vivactil (protriptyline) and Pamelor (nortriptyline) and the mood stabilizer Trileptal (oxcarbazepine).
A Word From Verywell
For a number of reasons, then, the bottom line with St. John’s wort for persons with manic-depressive illness should be “better safe than sorry.” If you or someone you love who is bipolar insists on using this supplement, use extreme caution. Notify your physician or psychiatrist, and be on the lookout for any complications and changes in mood or behavior that could be dangerous.
