Acetyl-L-Carnitine

Carnitine is derived from an amino acid and may be made by health individuals. Carnitine is concentrated in tissues that oxidize fatty acids as a dietary fuel. It plays a critical role in energy production. It is an essential cofactor that helps transport long-chain fatty acids into the mitochondria so that they can be oxidized to produce energy in the form of adenosine triphosphate (ATP)¹. Carnitine also helps transport some toxic compounds out of the mitochondria¹.

Reference:

1. Belay B, Esteban-Cruciani N, Walsh CA, Kaskel FJ. The use of levo-carnitine in children with renal disease: a review and a call for future studies. Pediatr Nephrol 2006;21:308-17

Healthy people’s bodies can make all the carnitine they need. Therefore, carnitine is not an essential nutrient, and experts haven’t set a recommended daily amount

Carnitine supplements may show benefits in the following areas. 

Alzheimer’s disease and dementia:

Studies have shown that carnitine might help people with mild dementia or Alzheimer’s disease, with some short-term improvements

Insulin resistance and diabetes:

Insulin resistance is a condition in which your body doesn’t properly use insulin, a hormone that controls blood glucose (also called blood sugar) levels. Insulin resistance increases the risk of type 2 diabetes. Some studies have found that carnitine supplements might help the body use insulin more effectively and might decrease blood glucose and A1C levels. Other studies have shown that carnitine might reduce cholesterol, but not triglyceride, levels in people with diabetes. 

Osteoarthritis:

Studies of carnitine have shown it may help reduce knee pain in middle-age women with osteoarthritis. 

Weight loss: 

Because carnitine helps turn the food you eat into the energy you need, studies of carnitine supplements may help people lose weight. 

Many foods, especially animal foods, naturally contain carnitine. These include the following: 

• Red meat is a good source of carnitine. 
• Poultry, fish, and dairy have some carnitine. 
• Vegetables, fruits have very small amounts of carnitine
• Grains have very small amounts of carnitine

Several types of medications have the potential to interact with carnitine supplements. A few examples are provided below. People taking these and other medications on a regular basis should discuss their carnitine intake with their healthcare providers. 

Pivalate-conjugated antibiotics 

Carnitine interacts with pivalate-conjugated antibiotics, such as pivampicillin, that are used to prevent urinary tract infections [1]]. Chronic administration of these antibiotics can lead to carnitine depletion. However, although tissue carnitine levels in people who take these antibiotics may become low enough to limit fatty acid oxidation, no cases of illness due to carnitine deficiency in this population have been described [2,3,4]. 

Valproic acid and other anticonvulsants 

Treatment with the anticonvulsants valproic acid, phenobarbital, phenytoin, and carbamazepine reduces blood levels of carnitine [5,6,7,8]. In addition, the use of valproic acid with or without other anticonvulsants may cause hepatotoxicity and increase plasma ammonia concentrations, leading to encephalopathy [7,8]. This toxicity may also occur after acute valproic acid overdoses. Intravenous L-carnitine administration might help treat valproic acid toxicity in children and adults, although the optimal regimen has not been identified [8,9,10]. 

References:

1. Brass EP. Pivalate-generating prodrugs and carnitine homeostasis in man. Pharmacol Rev 2002;54:589-98
2. Rebouche CJ. Carnitine. In: Shils ME, Olson JA, Shike M, et al., eds. Modern Nutrition in Health and Disease, 9th ed. New York, NY: Lippincott Williams & Wilkins, 1999:505-12.
3. Rebouche CJ. Kinetics, pharmacokinetics, and regulation of L-carnitine and acetyl-L-carnitine metabolism. Ann NY Acad Sci 2004;1033:30-41.
4. Hug G, McGraw CA, Bates SR, Landrigan EA. Reduction of serum carnitine concentrations during anticonvulsant therapy with phenobarbital, valproic acid, phenytoin, and carbamazepine in children. J Pediatr 1991;119:799-802. [PubMed abstract]
5. Castro-Gago M, Eiris-Punal J, Novo-Rodriguez MI, Couceiro J, Camina F, et al. Serum carnitine levels in epileptic children before and during treatment with valproic acid, carbamazepine, and phenobarbital. J Child Neurol 1998;13:546-9. [PubMed abstract]
6. Verrotti A, Greco R, Morgese G, Chiarelli F. Carnitine deficiency and hyperammonemia in children receiving valproic acid with and without other anticonvulsant drugs. Int J Clin Lab Res 1999;29:36-40. [PubMed abstract]
7. Kobayashi H, Fukuda S, Yamada K, Hasegawa Y, Takahashi T, et al. J Clinical features of carnitine deficiency secondary to pivalate-conjugated antibiotic therapy. Pediatr 2016;173:183-7.
8. Lheureux PE, Hantson P. Carnitine in the treatment of valproic acid-induced toxicity. Clin Toxicol (Phila) 2009;47:101-11
9. U.S. Food and Drug Administration. Search Orphan Drug Designations and Approvals . November 1989.
10. Perrott J, Murphy NG, Zed PJ. L-carnitine for acute valproic acid overdose: a systematic review of published cases. Ann Pharmacother 2010;44:1287-93.

Always read the label. Follow the directions for use. If symptoms persist, consult your healthcare professional. Vitamin supplements should not replace a balanced diet. If you have any pre-existing conditions, or are on any medications always talk to your health professional before use. Store your daily packs below 25°C in a cool, dry place, away from humidity and direct sunlight.