Can i take levothyroxine with other meds
Pro Research Analysisby 
Searched over 200M research papers
Can I Take Levothyroxine with Other Medications?
Levothyroxine is a commonly prescribed medication for treating hypothyroidism. However, its absorption and efficacy can be significantly affected by the concurrent intake of other medications and certain foods. This article explores the interactions between levothyroxine and other substances, providing guidance on how to manage these interactions effectively.
Medications That Decrease Levothyroxine Absorption
Phosphate Binders and Nutritional Supplements
Certain medications can interfere with the absorption of levothyroxine by forming insoluble complexes in the intestinal lumen. For instance, sevelamer hydrochloride, a phosphate binder used to treat hyperphosphatemia, and chromium picolinate, a nutritional supplement, have been shown to significantly decrease the absorption of levothyroxine. Patients taking these medications should separate their ingestion from levothyroxine by several hours to avoid reduced efficacy1.
Calcium and Iron Supplements
Calcium and iron supplements are also known to impair the bioavailability of levothyroxine. These supplements can form insoluble complexes with levothyroxine, reducing its absorption. It is recommended to maintain a proper time interval between the intake of levothyroxine and these supplements to mitigate this interaction2 4.
Proton Pump Inhibitors and Bile Acid Sequestrants
Proton pump inhibitors, which increase the pH of gastric acid, and bile acid sequestrants can also interfere with levothyroxine absorption. These medications should be taken at different times from levothyroxine to ensure optimal absorption and efficacy4.
Food and Beverage Interactions
Coffee, Soy Products, and Fiber
The ingestion of levothyroxine with certain foods and beverages can alter its pharmacokinetics and pharmacodynamics. Coffee, soy products, and high-fiber foods have been shown to decrease the absorption of levothyroxine. Patients are advised to take levothyroxine on an empty stomach, at least 30 minutes before breakfast, to avoid these interactions2.
Milk, Juices, and Papaya
Milk, certain juices, and papaya can also affect the absorption of levothyroxine. These foods should be consumed at a different time from levothyroxine to prevent reduced efficacy2.
Recommendations for Safe Co-Administration
Timing and Formulation Adjustments
To minimize interactions, it is crucial to separate the intake of levothyroxine from other medications and certain foods by several hours. Additionally, novel formulations of levothyroxine, such as liquid solutions and soft-gel capsules, may help eliminate malabsorption issues caused by chelation and alkalization2 4.
Monitoring and Dose Adjustments
Regular monitoring of thyroid function tests is essential for patients taking levothyroxine alongside other medications or dietary supplements. Dose adjustments may be necessary to maintain optimal thyroid hormone levels and ensure effective treatment4.
Conclusion
While levothyroxine is an effective treatment for hypothyroidism, its absorption can be significantly affected by other medications and certain foods. By understanding these interactions and managing the timing of ingestion, patients can optimize the efficacy of their levothyroxine therapy. Regular monitoring and potential dose adjustments are also crucial to ensure effective treatment outcomes.
Sources and full results
Most relevant research papers on this topic
New medications which decrease levothyroxine absorption.
Hypothyroid patients taking sevelamer hydrochloride or chromium picolinate should separate their drug intake from their thyroid hormone preparation by several hours.
Non-RCT
Highly CitedLevothyroxine Interactions with Food and Dietary Supplements–A Systematic Review
Levothyroxine ingestion in the morning and at bedtime is equally effective, but interactions with coffee, soy products, fiber, calcium, or iron supplements can decrease its absorption.
Systematic ReviewREVIEW: Treatment of hypothyroidism with combinations of levothyroxine plus liothyronine.
Levothyroxine alone remains the treatment of choice for hypothyroidism replacement therapy until clear advantages of levothyroxine plus liothyronine are demonstrated.
Systematic ReviewHighly CitedMedications and Food Interfering with the Bioavailability of Levothyroxine: A Systematic Review
Many medications and foods can impair the bioavailability of levothyroxine, requiring awareness and dose adjustment for optimal treatment.
Systematic ReviewClinical Observation of Levothyroxine Sodium Combined with Selenium in the Treatment of Patients with Chronic Lymphocytic Thyroiditis and Hypothyroidism and the Effects on Thyroid Function, Mood, and Inflammatory Factors
Levothyroxine sodium combined with selenium treatment improves thyroid function, mood, and immune responses in chronic lymphocytic thyroiditis patients with hypothyroidism.
RCT
Rigorous JournalGuidelines for the treatment of hypothyroidism: prepared by the american thyroid association task force on thyroid hormone replacement.
Levothyroxine should remain the standard of care for treating hypothyroidism, as there is no consistently strong evidence to suggest alternative preparations improve health outcomes.
Rigorous JournalHighly CitedCombination treatment with T4 and T3: toward personalized replacement therapy in hypothyroidism?
Personalized thyroid hormone replacement therapy may improve quality of life, cognition, and peripheral thyroid hormone action in hypothyroid patients.
Systematic ReviewHighly CitedLevotyroxin.
Levothyroxine is a safe and effective treatment for hypothyroidism and thyroid cancer, with proper dosage and timing.
RF23 | PSAT258 Comparable Bioavailability of a Novel Levothyroxine Solution taken 10 or 30 minutes prior to a High-Fat, High-Calorie Breakfast
ThyquidityTM oral solution shows bioequivalence to Synthroid® when administered 10 or 30 minutes before a high-calorie, high-fat breakfast, making it a convenient option for patients.
RCTRigorous JournalAlternative schedules of levothyroxine administration.
Bedtime administration of levothyroxine is an option for patients with hypothyroidism who want to avoid taking their medication with food.
Systematic Review