Drug General Information (ID: DDIL9IDZ4U)
  Drug Name Levocarnitine Drug Info Warfarin Drug Info
  Drug Type Small molecule Small molecule
  Therapeutic Class Nutritional Supplements Anticoagulants
  Structure

 Mechanism of Levocarnitine-Warfarin Interaction (Severity Level: Moderate)
     Increased risk of bleeding Click to Show/Hide Mechanism Graph
Could Not Find 2D Structure
      Drug Name Levocarnitine Warfarin
      Mechanism Potentiate the hypoprothrombinemic effect of vitamin K antagonist Vitamin K antagonist
      Key Mechanism Factor 1
Factor Name Bleeding
Factor Description Patients may be at risk for bleeding when the outcome of a disease or disease treatment confounds the standard mechanisms for maintaining hemostasis. Signs or symptoms of abnormal bleeding include: bleeding that takes a long time to stop (including nosebleeds, bleeding gums, bleeding from cuts and abrasions, and menstrual bleeding); severe unexplained bruising, or bruising that becomes larger; blood in the urine or stool, etc.
      Mechanism Description
  • Increased risk of bleeding by the combination of Levocarnitine and Warfarin 

Recommended Action
      Management Caution is advised when coumarin anticoagulants are used with levocarnitine. The INR should be checked frequently and anticoagulant dosage adjusted accordingly, particularly following initiation, discontinuation, or change of dosage of levocarnitine. Patients should be advised to promptly report any signs of bleeding to their doctor, including pain, swelling, headache, dizziness, weakness, prolonged bleeding from cuts, increased menstrual flow, vaginal bleeding, nosebleeds, bleeding of gums from brushing, unusual bleeding or bruising, red or brown urine, or red or black stools.

References
1 Guo LQ, Yamazoe Y "Inhibition of cytochrome P450 by furanocoumarins in grapefruit juice and herbal medicines." Acta Pharmacol Sin 25 (2004): 129-36. [PMID: 14769198]
2 Bachmann HU, Hoffmann A "Interaction of food supplement L-carnitine with oral anticoagulant acenocoumarol." Swiss Med Wkly 134(25-26) (2004): 385. [PMID: 15340883]
3 Product Information. Carnitor (levocarnitine). Sigma-Tau Pharmaceuticals, Gaitherburg, MD.