levothroid and Amobarbital Interactions

Interactions between levothroid(levothyroxine) and Amobarbital (amobarbital)

amobarbital and levothyroxine (Moderate Drug-Drug)

MONITOR: Barbiturates may decrease exogenous thyroid plasma concentrations resulting in elevated thyroid stimulating hormone (TSH) and exacerbation of hypothyroidism. The mechanism may be induction of hepatic CYP450 enzymes responsible for thyroxine (T4) and triiodothyronine (T3) metabolism. Clinical data are limited.

MANAGEMENT: Clinical monitoring of patient response, including laboratory serum TSH concentrations, is recommended. Adjustment of thyroid replacement dosage may be indicated when initiating or discontinuing barbiturate therapy.