Chat with Pharmacy Staff


How do you take levothyroxine?


Unless your doctor has given you alternate instructions, administer on an empty stomach with a full glass of water at least 30 - 60 minutes before breakfast. Administer 4 hours apart from medications known to decrease absorption such as vitamin and mineral supplements and antacids. Oral aluminum hydroxide, magnesium salts, calcium salts, calcium carbonate, and antacids, containing any of these electrolyte salts have been reported to decrease the absorption of thyroid medications. Some case reports have described clinical hypothyroidism resulting from coadministration of levothyroxine with oral calcium supplements and aluminum hydroxide. To minimize this interaction, administer levothyroxine at least 4 hours before or after antacids or other drugs containing aluminum, magnesium, or calcium.

Back to Pharmacist FAQs

If you're looking for more specific answers to specific questions, ask a Walgreens pharmacist here.

Answers to questions regarding information about medications or health conditions are not for diagnostic or treatment purposes and are not conclusive as to the presence or absence of any health condition. Consult your physician for diagnosis and treatment of your medical condition. The information provided is not a substitute for medical advice. Advances in medicine may cause this information to become outdated, invalid or subject to debate. Professional opinions and interpretations of the scientific literature may vary. Walgreens' terms of use and general warranty disclaimer apply to all services provided. If you are in need of immediate medical attention, contact your physician, poison control center or emergency medical professional. If you need to speak with a pharmacist for non-emergency matters, contact your local Walgreens pharmacist or call a Walgreens.com pharmacist toll-free at 1 (877) 250-5823.