S-Adenosyl-L-Methionine (SAMe)

S-adenosyl-L-methionine (SAMe) is a naturally occurring chemical in the human body, produced largely by the liver. It is also manufactured synthetically as a supplement.

(See also Overview of Dietary Supplements Overview of Dietary Supplements Dietary supplements are used by about 75% of Americans. They are the most common therapies included among integrative medicine and health (IMH) and complementary and alternative medicine (CAM)... read more .)

SAMe is said to be effective in treating depression Depression Depression is a feeling of sadness and/or a decreased interest or pleasure in activities that becomes a disorder when it is intense enough to interfere with functioning. It may follow a recent... read more , osteoarthritis Osteoarthritis (OA) Osteoarthritis is a chronic disorder that causes damage to the cartilage and surrounding tissues and is characterized by pain, stiffness, and loss of function. Arthritis due to damage of joint... read more , and gallbladder and liver disorders. It may help people who have osteoarthritis function better. Some people also claim that SAMe may help treat attention-deficit/hyperactivity disorder Attention-Deficit/Hyperactivity Disorder (ADHD) Attention-deficit/hyperactivity disorder (ADHD) is poor or short attention span and/or excessive activity and impulsiveness inappropriate for the child’s age that interferes with functioning... read more (ADHD) and fibromyalgia Fibromyalgia Fibromyalgia is characterized by poor sleep, fatigue, mental cloudiness, and widespread aching and stiffness in soft tissues, including muscles, tendons, and ligaments. Poor sleep, stress, strains... read more .

Scientific studies so far do not clearly confirm that SAMe has most of its claimed benefits and more research is needed.

However, in 2 studies reviewed in a 2002 analysis SAMe was shown to be as effective as nonsteroidal anti-inflammatory drugs (NSAIDs) in treating people with osteoarthritis, but without the side effects common with NSAID use.

In some studies, SAMe used in combination with an antidepressant was useful for people who had depression that did not abate with treatment using a selective serotonin reuptake inhibitor Selective serotonin reuptake inhibitors (SSRIs) Agomelatine, a new type of antidepressant, is a possible treatment for major depressive episodes. Several types of drugs can be used to treat depression: Selective serotonin reuptake inhibitors... read more (SSRI), but this benefit was not confirmed in later studies.

No serious side effects have been reported. People with a bipolar disorder should not use SAMe, because it can cause manic episodes.

Some less serious side effects that have been reported include digestive problems, as well as dry mouth, headache, dizziness, and skin rashes.

Combining certain antidepressant drugs, such as clomipramine, with SAMe may increase serotonin levels, which may cause serotonin syndrome Serotonin Syndrome Serotonin syndrome is a potentially life-threatening drug reaction that tends to cause high body temperature, muscle spasms, and anxiety or delirium. Serotonin is a chemical that transmits impulses... read more , a serious disorder characterized by fever, confusion, rapid heart rate, anxiety, tremors, and other symptoms. SAMe may also decrease levodopa levels (deficient in people who have Parkinson disease Parkinson Disease (PD) Parkinson disease is a slowly progressive degenerative disorder of specific areas of the brain. It is characterized by tremor when muscles are at rest (resting tremor), increased muscle tone... read more ) and thus decrease the effectiveness of drugs that aim to treat Parkinson disease by increasing levodopa levels.

SAMe seems to be a useful treatment for osteoarthritis and may help relieve depression. The American Psychiatric Association states that SAMe is an option in people who prefer natural treatments. The Canadian Network for Mood and Anxiety Treatments states that SAMe may be considered a first- or second-line treatment for mild to moderate depression. Other claimed benefits require more evidence for confirmation.

People who plan to take SAMe with certain antidepressants such as clomipramine should talk to their doctor about the risks, because serotonin levels may increase and result in serotonin syndrome. People with Parkinson disease should avoid SAMe because it may decrease the benefit of certain drugs used to treat Parkinson disease. Overall, SAMe appears to be safe for most people.