Drug General Information (ID: DDIFDUQV5K)
Drug Name			Amitriptyline		Drug Info		Levothyroxine		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Analgesics				Antithyroid Agents
Structure

Mechanism of Amitriptyline-Levothyroxine Interaction (Severity Level: Moderate)
Potentiated the pharmacological effects (Unspecific) Click to Show/Hide Mechanism Graph
Drug Name		Amitriptyline				Levothyroxine
Mechanism 1		Tricyclic antidepressants				Potentiate the effects of tricyclic antidepressant by increasing the sensitivity of receptors to catecholamines
Key Mechanism Factor 1
		Factor Name		Pharmacodynamics
		Factor Description		Enhanced pharmacological effects leading to increased adverse reactions.
Mechanism Description		Potentiate the pharmacologic effects by the combination of Amitriptyline and Levothyroxine
Mechanism 2		Tricyclic antidepressant				Potentiate the effects of tricyclic antidepressant by increasing the sensitivity of receptors to catecholamines
Key Mechanism Factor 2
		Factor Name		Pharmacodynamics
		Factor Description		Enhanced pharmacological effects leading to increased adverse reactions.
Mechanism Description		Potentiate the pharmacologic effects by the combination of Amitriptyline and Levothyroxine

Recommended Action
Management		Patients receiving concomitant thyroid hormone replacement therapy and tricyclic antidepressant therapy should be closely monitored for cardiac arrhythmias and CNS stimulation. Advise patients to contact their doctor if they experience toxicity symptoms such as: anxiety, agitation, insomnia, shortness of breath, irregular or fast heartbeat, and lightheadedness or dizziness.

References
1	Product Information. Synthroid (levothyroxine). Abbott Pharmaceutical, Abbott Park, IL.
2	Product Information. Triostat (liothyronine). JHP Pharmaceuticals, Saddle River, NJ.
3	Goodwin FK, Prange AJ Jr, Post RM, Muscettola G, Lipton MA "Potentiation of antidepressant effects by L-triiodothyronine in tricyclic nonresponders." Am J Psychiatry 139 (1982): 34-8