Carnitine
Carnitine (vitamin B13) is a protein found in all tissues and is essential in mammalian energy metabolism. It facilitates the entry of long-chain fatty acids into the mitochondria of the cells thereby delivering substrate, which are acted upon by enzymes, for oxidation and subsequent energy production. Humans obtain it from food, including red meat, milk and milk products; it is also produced by the body from the dietary amino acids, lysine and methionine. Most carnitine (90-98%) is stored in skeletal and cardiac muscles, at levels roughly 10 times higher than the levels found in the blood.
Plasma carnitine levels are decreased in many people with epilepsy. This carnitine deficiency may result from nutritional factors, underlying metabolic disorders, or the effects of drugs and diseases, alone or in combination. Plasma levels are usually lowest in people taking a combination of valproate with other anti-epileptic drugs (AEDs) such as phenobarbital, phenytoin or carbamazepine (valproate polypharmacy), though taking valproate alone or other AEDs alone may sometimes cause a deficiency. Studies suggest that a young age and multiple disabilities may be risk factors for carnitine deficiency as well.
Carnitine is used for a small percentage of people who are at risk of liver damage from AEDs and is used for children with multiple seizure types who are taking multiple AEDs. It may be "strongly recommended" for persons with epilepsy whose carnitine levels are low due to taking valproate; or if there is an increased level of ammonia (hyperammonemia) from taking valproate; for young children with complex neurologic disorders who are taking multiple AEDs; and for people on the ketogenic diet (where it may promote ketosis) who have low plasma levels of carnitine. It may be prescribed to those on dialysis. Carnitine is used in emergency situations where there is liver damage caused by valproate, or in cases of valproate overdose. It is used in rare diseases involving problems of the transport of carnitine into the mitochondria.
Adverse effects may include transient nausea, vomiting, abdominal cramps and diarrhea. Less frequent reactions may include body odour or gastrointestinal symptoms.
Although animal studies show no evidence of infertility or foetal harm due to carnitine, no valid data are available for human pregnancies. It is not known whether it is excreted in milk.
In Canada, Carnitor (carnitine) is available in two forms, prescription drugs and non-prescription supplements. The prescription formula is more expensive, it is generally recommended because carnitine supplements are less regulated and are not always made purely with biologically active compounds, which may cause some side effects and interfere with medication.
Disclaimer
The material offered at this site is to provide general information about epilepsy to the public. It is not intended to be taken as medical advice. Although all material presented at this site has been thoroughly researched and is believed to be correct, Epilepsy Ontario accepts no liability. Consult your physician and/or neurologist with any questions you have. People with epilepsy should never discontinue anti-epileptic medications or make changes in activities unless specifically advised to do so by an attending physician.
