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Supplements: Weighing Benefits and Risks

Most grocery and drug stores have entire aisles dedicated to complementary and alternative medicines like vitamins and supplements, there are even entire stores dedicated to selling these kinds of specialty products. If you can buy it over the counter, it must be safe, right? Not quite. While many supplements and alternative therapies are generally safe, they are not risk free, and some can cause dangerous reactions in situations of overuse, contamination, or interaction with other herbs or drugs.

If you are considering using complementary and alternative medicines (CAMs), it is important to make informed decisions, just as you would with any medication or treatment. Below are four common supplements used for mental health conditions to help you understand the potential benefits and risks.


Uses: Melatonin is a hormone associated with sleep. Melatonin is used as a treatment for mild to moderate sleep disorders, like difficulty falling asleep, insomnia and disturbed sleep. It can also be used to enhance sleep in healthy people.

Risks: Melatonin does not have many side effects, but it is often taken in doses that are too large, and people should “work up” to a therapeutic dose, beginning with .1-.2 mg per day. It is important to talk to your doctor if any prescription drug is being taken with melatonin. And it is especially important for people taking prescription sleeping pills, tranquilizers, benzodiazepines, barbiturates, narcotics, antidepressants, stimulants, blood thinners, glaucoma medication and/or beta blockers to discuss use of melatonin with a health professional.

St. John's Wort

Uses: St. John’s Wort is an herbal supplement known to be helpful as a short-term treatment for mild to moderate depression. It may also be useful for hypochondria and seasonal affective disorder. The typical dose for mild to moderate depression is 900 mg per day, split into three doses of 300 mg. You should always ask your doctor if it is ok to take St. John’s Wort and discuss any medications you are taking to make sure you won’t have any serious interactions.

Risks: St. John’s Wort has serious potential interactions with many prescription medications, including antidepressants. If you are taking medication for a mental health condition, such as an SSRI (some of the more common SSRIs include Prozac, Paxil and Zoloft), you should talk to your doctor about using St. John’s Wort because this combination can cause serotonin syndrome. Serotonin syndrome occurs when two substances that act on the brain chemical serotonin are taken at the same time. Symptoms vary, but typically start to appear within minutes or hours of combining medications or supplements and can include: overactive reflexes or muscle spasms, heavy sweating, agitation, fever, diarrhea, tremors, confusion and even hallucinations. If someone experiences the symptoms of serotonin syndrome, they should see a doctor immediately because it can be deadly if left untreated. St. John’s Wort is also suspected to decrease the effectiveness of birth control.

Omega-3 Fatty Acids

Uses: Omega-3 essential fatty acids (“omega-3s”)—most commonly associated with fish and fish oil—have been widely studied for their benefits for heart health and may help with mental health as well. While further research is needed, some studies suggest that omega-3s may be helpful in the treatment of depression and seem to have a mood-stabilizing effect. Omega-3 essential fatty acids may also help boost the effectiveness of conventional antidepressants.

Risks: Side effects and drug interactions are the same as eating fish, and are minimal. The most common side effect of omega-3 supplements is indigestion. If you experience indigestion while taking omega-3 or fish oil, try taking it with food and use smaller doses of the supplement at different times of day rather than taking it all at once.


Uses: SAM-e (S-adenosyl-L-methionine) is a naturally-occurring chemical present in all cells of the body. SAM-e has been approved as a prescription drug for depression in some European countries. It is available without a prescription in the United States. SAM-e appears to be an effective treatment for depression, either by itself or used with other antidepressants, and may also be helpful for attention-deficit/hyperactivity disorder (ADHD).

Risks: SAM-e can worsen underlying agitation, panic, or anxiety as it begins working, and those taking medication for mental health conditions should check with their doctor before using SAM-e, as there could be serious side effects from interactions.

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