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L-Carnitine

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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: 990 mg two to three times daily in tablets or as an oral solution.
  • For chest pain (angina): Doses of 900 mg to 2 grams of L-carnitine have been taken in one to two divided doses daily for 2 weeks to 6 months.
  • For heart failure: 1.5 to 3.0 grams of L-carnitine has been taken in one to two divided doses daily for up to about 34 months. A specific product (Carni Q-Gel, Tishcon Corporation,Westbury, NY) containing 2250 mg of carnitine and 270 mg of coenzyme Q10 has been taken daily for 12 weeks.
  • For people with serious kidney disease undergoing hemodialysis: Doses of 0.64-3 grams or 10 mg/kg of L-carnitine has been used daily for 3-52 weeks. Taking L-carnitine by mouth is not FDA approved to treat carnitine deficiency in people with serious kidney disease.
  • For high thyroid hormone levels (hyperthyroidism): 2-4 grams of L-carnitine has been taken daily for 2-4 months.
  • For male infertility: 2-3 grams of L-carnitine has been taken in up to three divided doses daily, with or without vitamin E, for 2 to 24 weeks. Also, 2 grams of L-carnitine plus 1 gram of acetyl-L-carnitine has been taken daily, with or without a 300 mg cinnoxicam suppository every 4 days, for 3-6 months.
  • For inflammation of the heart (myocarditis): 100 mg/kg of D,L-carnitine has been taken daily for 4 days.
  • For preventing side effects caused by valproic acid (Depacon, Depakene, Depakote, VPA): 50 to 100 mg/kg has been taken in three or four divided doses daily up to a maximum of 3 grams daily.
BY IV:
  • For chest pain (angina): An infusion of 3 grams of L-carnitine in 500 mL of 5% dextrose has been given once daily for 14 days. 40mg/kg of D,L-carnitine has also been given by IV 30 minutes before exercise.
  • For L-carnitine deficiencies: Doses of 50 mg/kg of L-carnitine have been given as a slow injection or by infusion followed by 50 mg/kg of L-carnitine in divided doses every 3 to 4 hours over the next 24 hours. In the following days, daily maintenance doses are usually in the range of 50 mg/kg. For people with L-carnitine deficiency related to hemodialysis, 10 to 20 mg/kg of L-carnitine adjusted for L-carnitine blood levels is used.
  • For heart failure: 5 grams of L-carnitine has been given by IV daily for 7 days in addition to conventional treatment.
  • For serious kidney disease: Doses of 10 to 20 mg/kg of L-carnitine given as a slow injection is FDA-approved for use for L-carnitine deficiency in people with serious kidney disease. For treating disorders related to low levels of carnitine in hemodialysis patients, 1.8 grams of L-carnitine weekly to 3 grams daily or 30-120 mg/kg/week have been given by IV for 2 weeks to 12 months. Doses were usually given three times weekly after dialysis sessions. Also, 1 gram of L-carnitine has been given by IV three times weekly after each dialysis session together with 100 mg of coenzyme Q10 taken by mouth daily for 3 months.
  • For preventing side effects caused by valproic acid (Depacon, Depakene, Depakote, VPA): 150-500 mg/kg has been taken daily. A maximum of 3 grams daily.

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