This page explains what happens if Amitriptyline and Levothyroxine are taken together, according to official sources.
Increased risk of cardiac arrhythmias and tachycardia
Concomitant levothyroxine and amitriptyline can heighten cardiac receptor sensitivity, triggering sinus tachycardia and ventricular arrhythmias.
Monitor heart rate, rhythm, and blood pressure carefully, particularly in patients with pre-existing ischemic heart disease.
Last updated: Sep 25, 2026
Before changing or stopping any medicine, ask your doctor or pharmacist. Never stop your medicine on your own.