Drug General Information (ID: DDIARVKW4G)
Drug Name			Digoxin		Drug Info		Levothyroxine		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antiarrhythmic Agents				Antithyroid Agents
Structure

Mechanism of Digoxin-Levothyroxine Interaction (Severity Level: Moderate)
Increased renal excretion (Unspecific) Click to Show/Hide Mechanism Graph
Drug Name		Digoxin				Levothyroxine
Mechanism		Digitalis glycosides				Increased clearance or sensitivity of digitalis glycosides
Key Mechanism Factor 1
		Factor Name		Pharmacokinetics
		Factor Description		Alters the excretion of the drug, resulting in changes in the plasma concentration of the drug and affecting the pharmacological effects.
Mechanism Description		Increased renal excretion of Digoxin caused by Levothyroxine

Recommended Action
Management		Monitor the patient closely for altered efficacy and safety while achieving a euthyroid state or when thyroid hormones are added, discontinued, or dosing changes are made. Digitalis dose increases may be required.

References
1	Frye RL, Braunwald E "Studies on digitalis. III: The influence of triiodothyronine on digitalis requirements." Circulation 23 (1961): 376-82. [PMID: 13702336]
2	Huffman DH, Klaassen CD, Hartman CR "Digoxin in hyperthyroidism." Clin Pharmacol Ther 22 (1977): 533-8. [PMID: 913019]
3	Lawrence JR, Sumner DJ, Kalk WJ, et al "Digoxin kinetics in patients with thyroid dysfunction." Clin Pharmacol Ther 22 (1977): 7-13. [PMID: 872497]