Do you take levothyroxine and can’t start your day without coffee? Good news—you don’t necessarily have to give coffee up. But you should know how coffee can change the way your thyroid medicine works and what to do so your dose stays effective.
When levothyroxine sits together with coffee in your stomach, the medicine can bind to compounds in the coffee or get pushed through your gut faster. A clinical study showed that taking levothyroxine at the same time as coffee significantly reduced how much hormone entered the bloodstream compared with taking it with water. That can lead to higher TSH and symptoms like fatigue or weight gain if it happens regularly.
Other things that lower levothyroxine absorption include calcium or iron supplements, antacids, soy products, and high-fiber meals. The main idea: anything that changes stomach content or binds the pill can cut how much medication you absorb.
Make your routine consistent. Two safe options work well for most people: take levothyroxine first thing in the morning with a full glass of water and wait 30–60 minutes before drinking coffee, or take your pill at bedtime (usually 3+ hours after dinner). Both approaches let the medicine be absorbed better.
If you accidentally had coffee right after your pill, don’t double up the next dose. Keep your normal schedule and note the mistake. If this happens often, tell your clinician and get TSH checked after 6–8 weeks—TSH is the lab that shows whether your dose is right.
Small changes to how you prepare coffee can help too. Avoid adding large amounts of milk or calcium-rich creamers right after taking your pill. If you use iron or calcium supplements during the day, separate them from levothyroxine by at least 4 hours.
If you’re switching from morning to bedtime dosing (or vice versa), expect your doctor to recheck labs. Absorption can improve with bedtime dosing, but labs are the only way to confirm the dose is still correct.
Final tip: stay consistent. The biggest risk isn’t one cup of coffee—it’s a shifting routine. Take your pill the same way every day, monitor symptoms, and follow up with TSH testing when your routine or medications change. If you’re unsure, reach out to your prescriber or pharmacist for personalized advice.
This article explores the potential impact of coffee on thyroid hormone absorption, particularly for those taking thyroid medications. It discusses the importance of timing medication intake, foods and beverages to avoid, and expert advice to optimize thyroid function.
