Medical expert of the article
New publications
What can carnitine deficiency lead to?
Last reviewed: 05.07.2025
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Carnitine deficiency results from inadequate intake or inability to utilize the amino acid carnitine. Carnitine deficiency is a heterogeneous group of disorders. Muscle metabolism is impaired, leading to myopathy, hypoglycemia, or cardiomyopathy. Treatment most often involves recommending a diet rich in L-carnitine.
The amino acid carnitine is necessary for the transport of coenzyme A esters and long-chain fatty acids, acetyl coenzyme A, into the myocyte mitochondria, where they are oxidized to produce energy. Carnitine is found in foods, especially those of animal origin, and is also synthesized in the body.
Causes of Carnitine Deficiency
Causes of carnitine deficiency: inadequate intake [e.g., due to fad diets, unavailability of foods, total parenteral nutrition (TPN)]; failure to absorb due to enzyme deficiency (e.g., carnitine palmitoyltransferase deficiency, methyl malonate aciduria, propionate acidemia, isovaleriatemia); decreased endogenous carnitine synthesis in severe liver disease; excessive loss of carnitine in diarrhea, increased diuresis, hemodialysis; hereditary kidney disease in which carnitine is excreted excessively; increased need for carnitine in ketosis, an increased need for fatty acid oxidation; use of valproate. Carnitine deficiency may be generalized (systemic) or may affect primarily muscles (myopathic).
[ Symptoms of Carnitine Deficiency
Symptoms and the age at which symptoms appear depend on the cause of carnitine deficiency. Carnitine deficiency can lead to muscle necrosis, myoglobinuria, a so-called lipid myopathy, hypoglycemia, fatty liver disease, and hyperammonemia, which causes muscle pain, weakness, confusion, and cardiomyopathy.
In newborns, carnitine palmitoyltransferase deficiency is diagnosed by mass spectrometry. Prenatal diagnosis can be made by amniotic fluid (amniotic villous cells) analysis. In adults, definitive diagnosis of carnitine deficiency is made by measuring acyl-carnitine levels in serum, urine, and tissues (muscle and liver for systemic deficiency; muscle only for myopathic deficiency).
Treatment of carnitine deficiency
Carnitine deficiency, which results from inadequate dietary intake, increased requirements, excessive losses, decreased synthesis, and (sometimes) enzyme deficiencies, can be treated by administering L-carnitine at a dose of 25 mg/kg orally every 6 hours.