L-Carnitine

Are there any interactions with medications?



Acenocoumarol (Sintrom)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

Acenocoumarol (Sintrom) is used to slow blood clotting. L-carnitine might increase the effectiveness of acenocoumarol (Sintrom). Increasing the effectiveness of acenocoumarol (Sintrom) might slow blood clotting too much. The dose of your acenocoumarol (Sintrom) might need to be changed.



Thyroid hormone
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

L-carnitine seems to decrease how well thyroid hormone works in the body. Taking L-carnitine with thyroid hormone might decrease the effectiveness of the thyroid hormone.



Warfarin (Coumadin)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

Warfarin (Coumadin) is used to slow blood clotting. L-carnitine might increase the effects of warfarin (Coumadin) and increase the chances of bruising and bleeding. Be sure to have your blood checked regularly. The dose of your warfarin (Coumadin) might need to be changed.

Dosing considerations for L-carnitine.

The following doses have been studied in scientific research:

BY MOUTH:
  • For L-carnitine deficiencies in adults: 990 mg two to three times per day in tablets or as an oral solution.
  • For preventing side effects caused by valproic acid (Depacon, Depakene, Depakote, VPA): 50 to 100 mg/kg/day in three or four divided doses, to a maximum of 3 grams/day.
  • For chest pain and congestive heart failure (CHF): 1 gram twice daily.
  • Following heart attack: 2 to 6 grams daily.
  • For symptoms of overactive thyroid: 1-2 grams twice daily.
  • For male infertility: 2 grams of L-carnitine plus 1 gram of L-acetyl-carnitine daily.

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