SAMe (or S-adenosyl-L-methionine) is a naturally occurring chemical that is found throughout the entire body. It is involved in many chemical reactions that are necessary for life. SAMe is available as a natural dietary supplement that can be found at some pharmacies or health food stores, and can be purchased without a prescription.
Purpose
People take supplements of SAMe for many reasons including its possible antidepressant effects. Some evidence suggests that taking SAMe can improve symptoms of depression within two weeks, which is considerably faster than the time it takes for oral antidepressant prescription drugs to work. (Prescription antidepressants often take a minimum of two weeks for patients to begin noticing any effect, and many take four to six weeks.)
Description
SAMe is a specific form of the amino acid methionine, a substance that, when not metabolized properly, allows homocysteine to build up in the blood. SAMe is also an antioxidant, a substance that protects the body from damaging reactive oxygen molecules in the body. These reactive oxygen molecules can come from inside the body or from environmental pollution and are thought to play a role in the aging process and the development of degenerative disease. In general, SAMe is thought to raise the level of functioning of other amino acids in the body.
Several studies have indicated that oral SAMe and intravenous SAMe are effective treatments for depression. The studies researching the oral SAMe were small studies, and often were of short duration. However, the studies indicate that SAMe is effective in treating depression, and that it may be almost as effective as tricyclic antidepressants. Larger studies of SAMe are necessary.
Recommended dosage
SAMe can be taken orally or intravenously. Oral administration is more common. When taken by mouth, doses of 400–1,600 mg have been suggested. For osteoarthritis, 200–600 mg daily is a typical dose. For depression, 400–1,600 mg daily is a typical dose.
200 mg of SAMe have been administered intravenously or intramuscularly for 14 days while the patient simultaneously begins therapy with prescription antidepressant medication. If SAMe is used without prescription antidepressants, 200-400 mg per day by intravenous or intramuscular injections has been used. When treating other medical conditions, doses as high as 800 mg daily by injection have been used. Again, however, intravenous administration is rare in the United States.
Precautions
As a natural supplement, SAMe has not been evaluated by the Food and Drug Administration. Claims of safety or effectiveness for treating any medical disorder have not been thoroughly studied by any governmental
agency and there is no regulation of natural supplements. This means that potencies may vary between lots or among different manufacturers. It is also possible that supplements may not contain the ingredients that are listed on product labels.
SAMe should be used carefully by individuals with a history of bipolar disorder since it may aggravate symptoms of mania. When used with prescription antidepressant medications, life-threatening symptoms may occur. It should be used with prescription antidepressant drugs only under close medical supervision.
Side effects
When taken by mouth, SAMe may cause stomach upset including gas, vomiting, diarrhea, headache, and nausea. These symptoms are more common at high doses.
Anxiety has also occurred in people with depression, and mania has been reported in those with a history of bipolar disorder.
Interactions
As stated, use of SAMe with antidepressants (especially selective serotonin reuptake inhibitors, or SSRIs) may cause life-threatening symptoms including agitation, tremors, anxiety, rapid heartbeats, difficulty breathing, diarrhea, shivering, muscle stiffness, and excessive sweating. The combination can also cause insomnia. If SAMe is used at the same time that prescription antidepressants are taken, close medical supervision is required.
SAMe may offer beneficial drug interactions when used with some medications. More research is necessary to determine whether SAMe does indeed protect the liver, but some scientists think that SAMe may protect the liver from damage caused by some drugs, including acetaminophen, alcohol, estrogens, steroids, and several other prescription drugs.
People interested in taking SAMe for depression should discuss its use with their doctor to weigh the potential benefits and risks.
Fetrow, C. W., Pharm.D. and J. R. Avila, Pharm.D. "Efficacy of the dietary supplement S-adenosyl-L-methionine." Annals of Pharmacotherapy 35, no. 11 (November 2001): 1414-1425.
