Does Carnitor (levocarnitine) cause side effects?

Carnitor (levocarnitine) is a naturally occurring substance that the cells of mammals need to produce energy used to treat carnitine deficiency. 

Carnitine is a small protein that binds to and helps transport fatty acids into the mitochondria, the site of energy production within cells. In the mitochondria, carnitine binds to and removes toxins from the cells. 

Carnitine deficiency is a condition that prevents the body from using certain fats for energy and causes a variety of symptoms including severe brain dysfunction (encephalopathy), a weakened and enlarged heart (cardiomyopathy), muscle weakness, confusion, vomiting, and low blood sugar (hypoglycemia). Carnitor corrects low carnitine levels and reverses symptoms of carnitine deficiency.

Common side effects of Carnitor include

Serious side effects of Carnitor include

Drug interactions of Carnitor include warfarin, because the combination may increase the risk of bleeding by an unknown mechanism. If these drugs must be combined, the effect of warfarin treatment must be closely monitored and the dosage must be adjusted accordingly.

Carnitor has not been adequately studied in pregnant women. Carnitor should be used during pregnancy only if clearly needed. 

Carnitor supplementation has not been studied in nursing mothers, and it is not known whether Carnitor is excreted into breast milk. Consult your doctor before breastfeeding.

What are the important side effects of Carnitor (levocarnitine)?

Common side effects include:

Other reported side effects include:

Carnitor (levocarnitine) side effects list for healthcare professionals

Various mild gastrointestinal complaints have been reported during the long-term administration of oral L-or D,L-carnitine; these include

  • transient nausea and vomiting,
  • abdominal cramps, and
  • diarrhea.

Mild myasthenia has been described only in uremic patients receiving D,L-carnitine. Gastrointestinal adverse reactions with Carnitor (levocarnitine) Oral Solution or Carnitor SF (levocarnitine) Sugar-Free Oral Solution dissolved in liquids might be avoided by a slow consumption of the solution or by a greater dilution.

Decreasing the dosage often diminishes or eliminates drug-related patient body odor or gastrointestinal symptoms when present. Tolerance should be monitored very closely during the first week of administration, and after any dosage increases.

Seizures have been reported to occur in patients with or without pre-existing seizure activity receiving either oral or intravenous levocarnitine. In patients with pre-existing seizure activity, an increase in seizure frequency and/or severity has been reported.

What drugs interact with Carnitor (levocarnitine)?

Reports of INR increase with the use of warfarin have been observed. It is recommended that INR levels be monitored in patients on warfarin therapy after the initiation of treatment with levocarnitine or after dose adjustments.

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Medically Reviewed on 9/22/2020
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Professional side effects and drug interactions sections courtesy of the U.S. Food and Drug Administration.