Drug General Information (ID: DDI52N4IZF)
  Drug Name Ethinylestradiol Drug Info Dantrolene Drug Info
  Drug Type Small molecule Small molecule
  Therapeutic Class Estrogens Muscle Relaxants
  Structure

 Mechanism of Ethinylestradiol-Dantrolene Interaction (Severity Level: Major)
     Increased risk of hepatotoxicity Click to Show/Hide Mechanism Graph
Could Not Find 2D Structure
      Drug Name Ethinylestradiol Dantrolene
      Mechanism Hepatotoxicity Hepatotoxicity
      Key Mechanism Factor 1
Factor Name Hepatotoxicity
Factor Description Combination of drugs that can induce hepatotoxicity may increase the risk of liver injury. Symptoms vary depending on the level of exposure and the total extent of liver damage, and may cause few symptoms if the damage is mild, and eventually lead to liver failure in patients with severe damage.
      Mechanism Description
  • Increased risk of hepatotoxicity by the combination of Ethinylestradiol and Dantrolene 

Recommended Action
      Management Dantrolene should be used with caution in patients, particularly females over 35 years of age, who are receiving concomitant estrogen therapy. Liver function tests (SGOT, SGPT, alkaline phosphatase, total bilirubin) should be performed prior to and during dantrolene therapy at appropriate intervals, and the drug should generally be withheld if significant abnormalities are observed. Patients treated with dantrolene should be advised to promptly contact their physician if they develop signs and symptoms of hepatocellular injury such as fever, rash, anorexia, nausea, vomiting, fatigue, right upper quadrant pain, dark urine, and jaundice. The drug should be discontinued if hepatitis is suspected, since early detection and drug withdrawal will increase the likelihood of reversing the damage. Following resolution of clinical and laboratory abnormalities, reinstitution of dantrolene therapy should be attempted with extreme caution and only if benefit clearly outweighs the risk.

References
1 Fuhr U, Maier-Bruggemann A, Blume H, et al. "Grapefruit juice increases oral nimodipine bioavailability." Int J Clin Pharmacol Ther 36 (1998): 126-32. [PMID: 9562227]
2 Gunston GD, Mehta U "Potentially serious drug interactions with grapefruit juice." S Afr Med J 90 (2000): 41. [PMID: 10721388]
3 Product Information. Dantrium (dantrolene). Procter and Gamble Pharmaceutic, Cincinnati, OH.