Moderate interactionModerateSeparate by 1h

Coffee and Levothyroxine: interaction, severity and spacing

Coffee and Levothyroxine interact because coffee reduces levothyroxine absorption by up to 30% if drunk within an hour of the dose. Take them 1 hours apart. Moderate risk.

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

The interaction in detail

Summary of the Coffee and Levothyroxine interaction
PairCoffee and Levothyroxine
TypeFood interaction
SeverityModerate
Required spacing1 hours minimum
OnsetAt the time of dosing

Mechanism

Coffee reduces levothyroxine absorption by up to 30% if drunk within an hour of the dose.

What to do

Wait at least 60 minutes after levothyroxine before coffee.

Citationhttps://pubmed.ncbi.nlm.nih.gov/20303719/

How to fit both into one day

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 Coffee in the morning and Levothyroxine in the morning satisfies the 1-hour separation without disrupting either one's absorption window.

Coffee and Levothyroxine: common questions