Acetyl-L-carnitine: Can it relieve MS fatigue?

Some research suggests that acetyl-L-carnitine can improve fatigue associated with multiple sclerosis (MS), although more study is needed.

Acetyl-L-carnitine is a form of L-carnitine, an amino acid that is found in nearly all cells of the body. L-carnitine plays a critical role in the production of energy from long-chain fatty acids. In addition, it increases the activity of certain nerve cells in the central nervous system.

Fatigue is a common symptom in people with multiple sclerosis. The cause isn't well understood. A study published in 2006 evaluated the benefit of supplementation with L-carnitine in people with MS-related fatigue who had low blood levels of L-carnitine. Study participants were given 3 to 6 grams of oral L-carnitine daily. Researchers reported a decrease in fatigue intensity in 63 percent of participants treated with immunosuppressive drugs, especially in those treated with cyclophosphamide and interferon beta. Another study from 2004 showed that acetyl-L-carnitine seemed to improve fatigue in those with MS better than did amantadine, a drug commonly used to treat MS-related fatigue.

However, problems with the design of these studies make it unclear whether acetyl-L-carnitine is truly effective at reducing MS-related fatigue, and more study is needed.

Although acetyl-L-carnitine generally has only few or mild side effects, it can interfere with several medications, including anticoagulants, anticonvulsants, cephalosporins, penicillin derivatives, zidovudine and valproic acid. So talk to your doctor before starting acetyl-L-carnitine or any dietary supplement.