Acetyl-L-carnitine is a chemical compound that's made in the liver, kidneys and brain. It helps turn food into energy. And it eases the tissue-damaging process called oxidative stress. Acetyl-L-carnitine also is involved in nerve cell health.
In a few studies, people with diabetic neuropathy who took acetyl-L-carnitine supplements had less pain. They also had improvements in their ability to perceive vibrations, as well as improvements in nerve function tests. Some of these studies suggest that acetyl-L-carnitine eases pain better when people start taking it soon after diabetic neuropathy begins. But more research is needed.
In general, acetyl-L-carnitine supplements are thought to be safe when taken as directed. Side effects may include dry mouth, less appetite, trouble sleeping, headache and agitation.
Acetyl-L-carnitine supplements can affect certain medicines. Don't use these supplements if you take the blood thinner warfarin (Jantoven). Acetyl-L-carnitine can increase the effects of this medicine. That can raise the risk of bleeding. Also, don't use acetyl-L-carnitine if you take thyroid hormone medicine for hypothyroidism. The supplement might affect how well the thyroid medicine works.
Acetyl-L-carnitine supplements also might make some conditions worse, such as bipolar disorder. And if you've had seizures in the past, acetyl-L-carnitine may raise the risk for more seizures.