Depression is one of the top five conditions that people want to self-treat with non-drug therapies. St John’s wort (SJW) is one of the best known plant medicines. It is effective for a number of conditions, including mild to moderate depression.
SJW has been the subject of many clinical trials. Three meta-analyses (a statistical method to combine the results of many different studies) show that SJW is significantly more effective than placebo and equal to or better than the pharmaceutical anti-depressants examined in the studies.
There are not enough studies done with children for me to state with confidence that it is safe and effective. This as is often the case for prescription drugs as well, for obvious reasons. However, SJW is approved for treatment of depression in children and adolescents in Germany, where there is a long history of respecting and using botanical medicines.
Some people have been confused by two well-publicized “negative” studies conducted in the United States. In one study, SJW was not significantly different from placebo; in the second study, both SJW and a conventional antidepressant were not significantly different from placebo. There were important problems with these studies that were not made clear in most news reporting about them.
One problem was that the people used in one of these studies had moderate to severe depression while most studies of SJW look at people with mild to moderate depression. In addition, the research conducted by the National Institute for Health (NIH), used patients with long term, chronic depression of the sort that would not likely be properly treated by ANY medicine in the short time-frame that the study covered.
The other study was run by Pfizer, the maker of sertraline. Sertraline, also known as Zoloft, was the comparison drug in the NIH study. The Pfizer study had no comparison drug, which certainly diminished the value of the study. Most of us will want to look very very closely at the methods used and the conclusions drawn whenever a drug company publishes a negative study it has done on a product that rivals one of it’s own that it profits from.
Adverse effects associated with SJW are usually mild. They can include gastro-intestinal discomfort symptoms and fatigue. Some people may be more sun sensitive when using really large doses of SJW. A review of the safety reported in 20 clinical trials including 1787 patients found that the effective dose is 600-900 mg/day of 0.3% hypericin extract.
The risk of photosensitization at that dose was not statistically significant. Also, there have been no reported cases of monoamine oxidase inhibitor (MAOI) activity. So, unlike with many anti-depressant drugs, there is no need to restrict consumption of tyramine-containing foods, such as cheese and red wine.
There are SJW-drug interactions that are important to be aware of. In particular, SJW may decrease the effectiveness of oral contraceptives and increase the risk of unwanted pregnancy. The list of other possible drug interactions is extensive; however, most of the interactions are only theoretical or clinically insignificant.
A small number of drugs with a narrow therapeutic window that are known to interact with foods and other medications are problematic when mixed with SJW. You should always check with your physician before stopping a prescription drug or adding a new drug or herbal item to your daily routine.
The recommended dose is 300 mg three times per day of a standardized extract of 0.3% hypericin. You can take the entire dose in the morning if SJW is too stimulating or in the evening if you find it to be sedating. As with conventional antidepressants, it may take 3-4 weeks before significant effects are apparent.
Switching from conventional antidepressants to SJW can be safely done in patients with mild to moderate depression. You should work with a physician who knows how to make this switch in the way that works to protect your well being. A transition should take at least 4-6 weeks.
Most physicians will understand you need to use special caution when switching from an MAOI-type drug to SJW. For MAOI’s in general, there should be a 2-4 week washout period between stopping one and starting the other. Changes in medication should ALWAYS be discussed with a physician and made under the physician’s care.