Levocarnitine (levocarnitine)

Levocarnitine is a naturally occurring amino acid derivative essential for mammalian energy metabolism.

Levocarnitine is the synthetic L-isomer (biologic active form) of D,L-carnitine, a constituent of muscle tissue that plays an essential role in the metabolism of fatty acids. Carnitine is derived from 2 essential amino acids (lysine and methionine); it is synthesized in the liver and kidney, and found primarily in cardiac and skeletal muscle. The main dietary source of carnitine is meat products.

Carnitine acts as a carrier molecule facilitating long-chain fatty acid entry into cellular mitochondria, delivering substrate for oxidation and subsequent energy production. Fatty acids are utilized as an energy substrate in all tissues except the brain. In skeletal and cardiac muscle, fatty acids are the main substrate for energy production.

Levocarnitine may promote excretion of excess organic or fatty acids in patients with defects in fatty acid metabolism and/or specific organic acid metabolic disorders that result in accumulation of acyl-coenzyme A (acyl-CoA) esters. In patients with secondary carnitine deficiency, levocarnitine eliminates acyl-CoA compounds by promoting formation of acylcarnitine, which is quickly excreted. Levocarnitine increases plasma levocarnitine concentrations in patients with end-stage renal disease undergoing hemodialysis.

The absolute bioavailability of levocarnitine is about 15-16% following oral administration and correction for endogenous plasma levocarnitine concentrations. Peak plasma concentrations are attained 3.3-3.4 hours following oral administration. The rate and extent of distribution from plasma into erythrocytes appear to be minor or negligible.

Levocarnitine does not appear to bind to plasma proteins or albumin. The drug is metabolized principally to TMAO and gamma-butyrobetaine in the GI tract by bacteria. In healthy adults, approximately 9% of a dose is excreted in urine as levocarnitine (uncorrected for endogenous urinary excretion) following oral administration.

Approximately 58-65% of a dose is excreted (as levocarnitine and metabolites) in the urine and feces 5-11 days following oral administration of the radiolabeled drug to patients receiving a high carnitine diet and additional carnitine supplements for 15 days. About 4-8 and <1% of an administered radiolabeled dose is excreted in the urine as levocarnitine and in the feces as total carnitine, respectively. TMAO is principally excreted in the urine (8-49% of administered radiolabeled dose) and gamma-butyrobetaine is principally excreted in the feces (0.44-45% of administered radiolabeled dose).

Approximately 76% of a dose is excreted in the urine within 24 hours following direct IV injection.

USES: This medication is used to prevent and treat low blood levels of carnitine. Carnitine is a substance made in the body from meat and dairy products. It helps the body use certain chemicals (long-chain fatty acids) for energy and to keep you in good health.

Low blood levels of carnitine may occur in people whose bodies cannot properly use carnitine from their diets, people on dialysis due to serious kidney disease, and people being treated with certain drugs (such as valproic acid, zidovudine). Carnitine levels that are too low can cause liver, heart, and muscle problems. The injectable form of this drug is recommended if you have serious kidney disease (such as ESRD/dialysis) because high doses of the form taken by mouth may increase the risk of serious side effects.

Consult your doctor or pharmacist for details.

Generic name: levocarnitine
Pronunciation: (lee-voh-KAR-nih-teen)

The following indications are listed for Levocarnitine:

• Carnitine Deficiency

Also known as: Bt Factor Deficiency, Vitamin Bt Deficiency.

No ICD codes are available for this drug.