Moderate interactionModerateSeparate by 4h

Zinc picolinate and Levothyroxine: interaction, severity and spacing

Zinc picolinate and Levothyroxine interact because zinc chelates levothyroxine in the gut, lowering thyroid hormone absorption. Take them 4 hours apart. Moderate risk.

Last reviewed: 2026-09-20Reviewed by: StackingRight clinical review

The interaction in detail

Summary of the Zinc picolinate and Levothyroxine interaction
PairZinc picolinate and Levothyroxine
TypeNutrient–drug interaction
SeverityModerate
Required spacing4 hours minimum
OnsetAt the time of dosing

Mechanism

Zinc chelates levothyroxine in the gut, lowering thyroid hormone absorption.

What to do

Separate zinc from levothyroxine by at least 4 hours.

How to fit both into one day

Zinc picolinate
eveningwith food

Zinc taken with food reduces nausea but phytates block it, so use a chelated form. Sustain high doses only alongside copper.

Levothyroxine
morningempty stomach

Levothyroxine needs an empty stomach and gastric acid for full absorption. Take it 30-60 minutes before breakfast with plain water, and keep calcium, iron and coffee at least 4 hours away.

Putting Zinc picolinate in the evening and Levothyroxine in the morning satisfies the 4-hour separation without disrupting either one's absorption window.

Zinc picolinate and Levothyroxine: common questions