Epinephrine and Levothyroxine Interaction

Drug interaction information between Epinephrine and Levothyroxine.

Epinephrine and Levothyroxine have a documented minor interaction in FDA labeling.

FDA drug labeling documents a minor-severity interaction between Epinephrine and Levothyroxine. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.

Drug A

Epinephrine

Adrenergic Agonist

Drug B

Levothyroxine

Thyroid Hormone

How They Interact

Levothyroxine can make your heart and blood vessels more sensitive to epinephrine. This can cause the epinephrine to have a much stronger effect on your body than intended.

FDA Label Information

( 7 .1) Drugs that potentiate the effects of epinephrine include sympathomimetics, beta blockers, tricyclic antidepressants, MAO inhibitors, COMT inhibitors, clonidine, doxapram, oxytocin, levothyroxine sodium, and certain antihistamines.

Frequently Asked Questions

What SPL severity band is on file for Epinephrine + Levothyroxine?

Compiled FDA labeling labels this pair minor. That is a source-record field, not an individual medication-combination decision.

Which drug in this pair has the larger labeled-interaction portfolio?

Epinephrine has 28 labeled pairs on file vs Levothyroxine's 22. In the minor band specifically: Epinephrine has 24 (also Clonidine, Theophylline, Oxytocin, Amitriptyline); Levothyroxine has 22 (also Sertraline, Furosemide, Propranolol, Ferrous Sulfate).

What mechanism field is on file for Epinephrine and Levothyroxine?

Levothyroxine can make your heart and blood vessels more sensitive to epinephrine. This can cause the epinephrine to have a much stronger effect on your body than intended.

Epinephrine carries more major-labeled pairs than Levothyroxine

SPL source-record counts only. This page's band is minor · classes on file: Epinephrine (Adrenergic Agonist); Levothyroxine (Thyroid Hormone).

Epinephrine has 1 major-labeled pair vs Levothyroxine's 0. This page itself is in the minor band, not the major band.

Epinephrine

1 major · 3 moderate · 24 minor · 28 total

Levothyroxine

0 major · 0 moderate · 22 minor · 22 total

Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.