ACETYL-L-CARNITINE Overview Information
Acetyl-L-carnitine is an amino acid (a building block for proteins) that is naturally produced in the body. It helps the body produce energy.
Acetyl-L-carnitine is used for a variety of mental disorders including Alzheimer's disease, age-related memory loss, late-life depression, thinking problems related to alcoholism, and thinking problems related to Lyme disease. It is also used for Down syndrome, poor circulation in the brain, cataracts, nerve pain due to diabetes, nerve pain due to drugs used in the treatment of AIDS, and facial paralysis.
Some men use acetyl-L-carnitine for infertility, symptoms of “male menopause” (low testosterone levels due to aging), and a disease of the penis called Peyronie’s disease.
The body can convert L-carnitine to acetyl-L-carnitine and vice versa. But, no one knows whether the effects of acetyl-L-carnitine are from the chemical itself, from the L-carnitine it can make, or from some other chemical made along the way. For now, don’t substitute one form of carnitine for another.
How does it work?
Acetyl-L-carnitine helps the body produce energy. It is important for heart and brain function, muscle movement, and many other body processes.
Possibly Effective for:
- Improving memory problems in elderly people.
- Improving memory in people who use alcohol excessively. Taking acetyl-L-carnitine seems to improve memory in 30-60 year-old people whose use of alcohol has produced long-term thinking problems.
- Reducing nerve pain (neuropathy) caused by diabetes. Acetyl-L-carnitine reduces pain best in people who have not had diabetes for a long time or who have poorly controlled type 2 diabetes.
- Treating Peyronie’s disease, a connective tissue disease in men. Acetyl-L-carnitine seems to be more effective than a drug called tamoxifen for reducing pain and slowing worsening of the condition.
- Treating male infertility caused by inflammation of some reproductive organs and tissues (prostate, seminal vesicles, and epididymis). Taking acetyl-L-carnitine by mouth, along with L-carnitine for 6 months, seems to increase sperm count and sperm movement. The carnitines are used following 2 months of treatment with non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin.
- Treating symptoms of age-related testosterone deficiency (“male menopause”). Taking acetyl-L-carnitine by mouth along with propionyl-L-carnitine seems to help symptoms related to declining male hormone levels. This combination taken for 6 months seems to improve sexual dysfunction, depression, and fatigue in much the same way the male hormone testosterone does.
- Improving blood flow to the brain. Administering a single dose of acetyl-L-carnitine intravenously (by IV) seems to produce short-term improvements in blood flow in the brains of people who have poor blood circulation in the brain.
- Treating Alzheimer’s disease. Acetyl-L-carnitine is more likely to help those with early-onset Alzheimer’s disease who are less than 66 years of age and have a faster rate of disease progression and mental decline.
- Depression. Some research suggests acetyl-L-carnitine might improve mood and decrease depression in elderly people.
- Muscle weakness caused by medications taken for HIV disease. Some research suggests acetyl-L-carnitine might help relieve muscle weakness caused by some HIV treatments.
- Down syndrome.
- Thinking problems related to Lyme disease.
- Other conditions.
ACETYL-L-CARNITINE Side Effects & Safety
Acetyl-L-carnitine is LIKELY SAFE for most adults and POSSIBLY SAFE for most children when taken by mouth. It can cause some side effects including stomach upset, nausea, vomiting, dry mouth, headache, and restlessness. It can also cause a "fishy" odor of the urine, breath, and sweat.
Acetyl-L-carnitine is POSSIBLY SAFE for most adults when given by another route than by mouth. Use only under medical supervision.
Special Precautions & Warnings:Pregnancy and breast-feeding: Not enough is known about the use of acetyl-L-carnitine during pregnancy and breast-feeding. Stay on the safe side and avoid use.
Nerve pain (neuropathy) caused by chemotherapy: Acetyl-L-carnitine might worsen symptoms in some people with nerve pain caused by a class of chemotherapy drugs known as taxanes.
Under-active thyroid (hypothyroidism): There is some concern that acetyl-L-carnitine might interfere with thyroid hormone. Don't use acetyl-L-carnitine if you have an under-active thyroid.
Seizures: An increase in the number or seriousness of seizures has been reported in people with a history of seizures who have used L-carnitine by mouth or by IV (intravenously). Since L-carnitine is related to acetyl-L-carnitine, there is a concern that this might also occur with acetyl-L-carnitine. If you have ever had a seizure, don't take acetyl-L-carnitine.
Major Interaction Do not take this combination
- Acenocoumarol (Sintrom) interacts with ACETYL-L-CARNITINE
Acenocoumarol (Sintrom) is used to slow blood clotting. Acetyl-L-carnitine might increase the effectiveness of acenocoumarol (Sintrom). Increasing the effectiveness of acenocoumarol (Sintrom) might slow blood clotting too much. The dose of your acenocoumarol (Sintrom) might need to be changed.
Moderate Interaction Be cautious with this combination
- Warfarin (Coumadin) interacts with ACETYL-L-CARNITINE
Warfarin (Coumadin) is used to slow blood clotting. Acetyl-L-carnitine might increase the effects of warfarin (Coumadin) and increase the chances of bruising and bleeding. Be sure to have your blood checked regularly. The dose of your warfarin (Coumadin) might need to be changed.
The following doses have been studied in scientific research:
- For age-related memory loss: 1500-2000 mg of acetyl-L-carnitine has been used daily for 3 months.
- For age-related tiredness: 2 grams of acetyl-L-carnitine has been used twice daily for 180 days.
- For age-related testosterone deficiency: 2 grams of acetyl-L-carnitine plus 2 grams of propionyl-L-carnitine has been used daily for 6 months.
- For alcohol withdrawal: 1-3 grams of acetyl-L-carnitine has been administered by IV for 10 days. Then for the next 80 days, 3 grams of acetyl-L-carnitine has been taken by mouth daily.
- For Alzheimer's disease: 1500-3000 mg of acetyl-L-carnitine has been taken by mouth daily in two or three divided doses for 3-12 months.
- For improving memory in people who use alcohol excessively: 2 grams of acetyl-L-carnitine has been used daily for 90 days.
- For nerve pain in people with diabetes: 1500-3000 mg of acetyl-L-carnitine has been taken by mouth daily in divided doses for one year. In some cases, 1000 mg of acetyl-L-carnitine was injected into the muscles for 10-15 days before it was taken by mouth.
- For poor brain function in people with liver disease (hepatic encephalopathy): 2 grams of acetyl-L-carnitine has been taken twice daily for 90 days.
- For male infertility:
- 1 gram of acetyl-L-carnitine plus 2 grams of L-carnitine has been taken daily to treat male infertility
- For male infertility secondary to abacterial prostatovesiculoepididymitis: 500 mg of acetyl-L-carnitine plus 1 gram of L-carnitine every 12 hours has been used following 2 months of treatment with nonsteroidal anti-inflammatory drugs (NSAIDs).
- For male infertility due to low sperm movement: A combination containing 1660 mg of L-arginine, 150 mg of L-carnitine, 50 mg of acetyl-L-carnitine, and 200 mg of Panax ginseng has been taken daily for 3 months.
- For male infertility due to prostate swelling caused by Chlamydia infection: A combination containing 1660 mg of L-arginine, 150 mg of L-carnitine, 50 mg of acetyl-L-carnitine, and 200 mg of Panax ginseng has been taken daily for 6 months along with 600 mg of prulifloxacin.
- For Peyronie's disease: 1 gram of acetyl-L-carnitine has been taken twice daily for 3 months.
- For alcohol withdrawal: 1-3 grams of acetyl-L-carnitine has been given by IV over 3-4 hours for 10 days. Thereafter, 3 grams of acetyl-L-carnitine has been taken by mouth daily for 80 days.
- For improving blood flow to the brain: A single dose of 1500 mg of acetyl-L-carnitine has been given by IV.
- For nerve pain caused by diabetes: 1000 mg of acetyl-L-carnitine has been given as a shot daily for 10-15 days. In some cases, 2000 mg of acetyl-L-carnitine has been taken by mouth daily for 12 months following the shots.