Date Last Updated: 07/08/06
Back to Herbal Medicine page

Does St John's Wort improve symptoms of depression?

Treatment in brief
Extracts of the plant St. John’s Wort, have been used in folk medicine for a long time for a range of problems, including depression, anxiety and sleep problems.

The condition
Depression is common, serious and treatable. Untreated, it can result in disability and even death. It affects 1 in 25 people in any 1 month. It tends to be episodic and of varying severity. Symptoms develop over days to weeks, though there may be symptoms over the preceding months. Half respond to 6–8 weeks of active treatment. The likelihood of recovery decreases with the duration of symptoms. Some people with depression experience continuing symptoms and social and work problems. The more episodes of depression a person experiences, the more likely they are to experience a recurrence.

For the treatment of depression, a variety of antidepressant medications are available that have proven beneficial effects. Other treatments including cognitive behavioural therapy and interpersonal psychotherapy are also used. Treatment varies with type and severity of depressive symptoms. (RANZCP 2004)

Background
Extracts of the plant Hypericum perforatum L. (popularly called St. John’s Wort), have been used in folk medicine for a long time for a range of indications, including depressive disorders. Extracts of St. John’s Wort are licensed and widely used in Germany for the treatment of anxiety, depressive and sleep disorders. In recent years, St John’s Wort has also become very popular in other countries. St John’s Wort contains many substances that may contribute to its effects. The exact mechanism of action is still unclear. (Linde, Mulrow et al. 2005)

Depression is a condition that involves a significant and persistent lowering of mood associated with great sadness, and a loss of interest in life. Many people feel sad, discouraged, or "down" once in a while, but for some people, this mood does not go away. When these problems last two weeks or more, and are so bad that they get in the way of daily living, this is depression. http://www.infrapsych.com/root/1033/Depression/Depression_Symptoms.htm

Other symptoms include loss of interest and ability to experience pleasure, irritable rather than depressed or apathetic mood. The following physical symptoms may also be present: changes in appetite and weight, changes in sleep, and fatigue or loss of energy. Thinking may be affected with an increase in guilty and pessimistic thoughts, hopelessness and helplessness, Concentration may be affected and the person may become quite forgetful. Thoughts of death and suicide may be present. (RANZCP 2004)

The evidence
There is good evidence that St John’s Wort improves symptoms of mild to moderate depression. These people may not meet the criteria for major depression. The beneficial effects of St John’s Wort have been demonstrated in a systematic review of studies comparing this treatment to placebo and standard antidepressant treatment. Another two RCTs confirmed that St John’s Wort was more effective than placebo and one confirmed that St John’s Wort was as effective as a standard antidepressant. This finding was not supported by another RCT but this can be perhaps explained by the study being under-powered.

For major depression the evidence is inconclusive. The systematic review found a small benefit compared to placebo. One RCT found that St John’s Wort was as effective as a standard antidepressant. Another supported this finding but could not demonstrate a benefit for St John’s Wort or the standard antidepressant over placebo. This could be explained by poor methodological quality and a drop out rate of 47%.

There is good evidence that St John’s Wort extracts caused fewer side-effects than older antidepressant but a similar number to selective serotonin reuptake inhibitors.

Other important issues
Many patients buy St John’s Wort products from health-food stores and might not disclose this to their doctors. This can be problematic, because serious interactions can occur with a number of frequently used drugs http://www.medsafe.govt.nz/Profs/PUarticles/sjw.htm

The quality of Hypericum preparations can also differ considerably, and a number of products contain only minor amounts of bioactive constituents.

More studies that compare specific extracts with both placebo and standard antidepressants in clearly defined patient populations with and without major depression are needed.

Key messages

There is level 1 evidence that St John’s Wort is effective for mild or moderate depression.	1
There is level 4 evidence that St John’s Wort may be effective for major depression.	4
There is level 2 evidence that St John’s Wort extracts caused fewer side-effects than older antidepressant but a similar number to selective serotonin reuptake inhibitors.	2
There is no evidence about effectiveness in severe depression.	No study evidence
St John’s Wort extracts can have serious interactions with a variety of other drugs
People taking or considering taking St John’s Wort should inform their health care practitioner

Key: Levels of evidence

 

 

  

The information in this summary was developed by assessing:

Bjerkenstedt, L., G. V. Edman, et al. (2005). "Hypericum extract LI 160 and fluoxetine in mild to moderate depression: A randomized, placebo-controlled multi-center study in outpatients. [References]. European Archives of Psychiatry and Clinical Neuroscience 255(1): 40-47.

Fava, M., J. Alpert, et al. (2005). "A Double-blind, Randomized Trial of St John's Wort, Fluoxetine, and Placebo in Major Depressive Disorder. [References]." Journal of Clinical Psychopharmacology 25(5): 441-447.

Gastpar, M., A. Singer, et al. (2005). "Efficacy and Tolerability of Hypericum Extract STW3 in Long-term Treatment with a Once-daily Dosage in Comparison with Sertraline. [References]." Pharmacopsychiatry 38(2): 78-86.

Knuppel, L., J. Geddes, et al. (2004). "Adverse effects of St. John's Wort: a systematic review.[see comment]. [Review] [106 refs]." Journal of Clinical Psychiatry 65(11): 1470-9.

Linde, K., C. D. Mulrow, et al. (2005). "St John's wort for depression.[update of Cochrane Database Syst Rev. 2000;(2):CD000448; PMID: 10796719]. [Review] [100 refs]." Cochrane Database of Systematic Reviews 2.

Murck, H., M. Fava, et al. (2005). "Hypericum extract in patients with MDD and reversed vegetative signs: Re-analysis from data of a double-blind, randomized trial of hypericum extract, fluoxetine, and placebo. [References]." International Journal of Neuropsychopharmacology 8(2): 215-221.

Randlov, C., J. Mehlsen, et al. (2006). "The efficacy of St. John's Wort in patients with minor depressive symptoms or dysthymia--a double-blind placebo-controlled study." Phytomedicine 13(4): 215-21.

RANZCP (2004). "Australian and New Zealand clinical practice guidelines for the treatment of depression." Australian and New Zealand Journal of Psychiatry 38(6): 389-407.

Szegedi, A., R. Kohnen, et al. (2005). "Acute treatment of moderate to severe depression with hypericum extract WS 5570 (St John's wort): randomised controlled double blind non-inferiority trial versus paroxetine." Bmj 330(7490): 503-6.

Trautmann-Sponsel, R. D. and A. Dienel (2004). "Safety of Hypericum extract in mildly to moderately depressed outpatients: a review based on data from three randomized, placebo-controlled trials. [Review] [21 refs]." Journal of Affective Disorders 82(2): 303-7.

Uebelhack, R., J. Gruenwald, et al. (2004). "Efficacy and tolerability of Hypericum extract STW 3-VI in patients with moderate depression: a double-blind, randomized, placebo-controlled clinical trial." Advances in Therapy 21(4): 265-75.

Werneke, U., O. Horn, et al. (2004). "How effective is St John's wort? The evidence revisited." Journal of Clinical Psychiatry 65(5): 611-7.

 

Prepared: 14 July 2006

 

 

DISCLAIMER: This website does not provide specific medical advice and the information provided should not be used as a substitute for seeking medical advice from a registered health practitioner. Full disclaimer . . .