Sucralfate with Levothyroxine Interaction Details

Brand Names Associated with Sucralfate

Brand Names Associated with Levothyroxine

Medical Content Editor Dr. Brian Staiger, PharmD
Last updated Nov 25, 2023

Interaction Effect

Reduced efficacy of levothyroxine

Interaction Summary

Concomitant use of levothyroxine and sucralfate may decrease levothyroxine efficacy by binding to and delaying or preventing levothyroxine absorption, potentially resulting in hypothyroidism. If concurrent use of levothyroxine and sucralfate is required, administration of these agents should be separated by at least 4 hours. Consider monitoring TSH levels and/or other measures of thyroid function when sucralfate is initiated or discontinued during levothyroxine treatment.

Severity

Moderate

Onset

Unspecified

Evidence

Theoretical

How To Manage Interaction

Concomitant use of levothyroxine and sucralfate may result in reduced levothyroxine efficacy, which may result in hypothyroidism. If concurrent use is necessary, separate administration of these agents by at least 4 hours. Consider monitoring TSH levels and/or other measures of thyroid function when sucralfate is initiated or discontinued during levothyroxine treatment.

Mechanism Of Interaction

Decreased absorption of levothyroxine

Sucralfate Overview

• Sucralfate is used to treat and prevent the return of duodenal ulcers (ulcers located in first part of the small intestine). Treatment with other medications, such as antibiotics, may also be necessary to treat and prevent the return of ulcers caused by a certain type of bacteria (H. pylori) Sucralfate is in a class of medications called protectants. It sticks to damaged ulcer tissue and protects against acid and enzymes so healing can occur.

Levothyroxine Overview

• Levothyroxine is used to treat hypothyroidism (condition where the thyroid gland does not produce enough thyroid hormone). It is also used with surgery and radioactive iodine therapy to treat thyroid cancer. Levothyroxine is in a class of medications called hormones. It works by replacing thyroid hormone that is normally produced by the body.

• Without thyroid hormone, your body cannot function properly, which may result in poor growth, slow speech, lack of energy, excessive tiredness, constipation, weight gain, hair loss, dry, thick skin, increased sensitivity to cold, joint and muscle pain, heavy or irregular menstrual periods, and depression. When taken correctly, levothyroxine reverses these symptoms.

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Definitions

Severity Categories

Contraindicated

These drugs, generally, should not be used together simultaneously due to the high risk of severe adverse effects. Combining these medications can lead to dangerous health outcomes and should be strictly avoided unless otherwise instructed by your provider.

Major

This interaction could result in very serious and potentially life-threatening consequences. If you are taking this drug combination, it is very important to be under close medical supervision to minimize severe side effects and ensure your safety. It may be necessary to change a medication or dosage to prevent harm.

Moderate

This interaction has the potential to worsen your medical condition or alter the effectiveness of your treatment. It's important that you are monitored closely and you potentially may need to make adjustments in your treatment plan or drug dosage to maintain optimal health.

Minor

While this interaction is unlikely to cause significant problems, it could intensify side effects or reduce the effectiveness of one or both medications. Monitoring for changes in symptoms and your condition is recommended, and adjustments may be made if needed to manage any increased or more pronounced side effects.

Onset

Rapid: Onset of drug interaction typically occurs within 24 hours of co-administration.

Delayed: Onset of drug interaction typically occurs more than 24 hours after co-administration.

Evidence

Level of documentation of the interaction.

Established: The interaction is documented and substantiated in peer-reviewed medical literature.

Theoretical: This interaction is not fully supported by current medical evidence or well-documented sources, but it is based on known drug mechanisms, drug effects, and other relevant information.

How To Manage The Interaction

Provides a detailed discussion on how patients and clinicians can approach the identified drug interaction as well as offers guidance on what to expect and strategies to potentially mitigate the effects of the interaction. This may include recommendations on adjusting medication dosages, altering the timing of drug administration, or closely monitoring for specific symptoms.

It's important to note that all medical situations are unique, and management approaches should be tailored to individual circumstances. Patients should always consult their healthcare provider for personalized advice and guidance on managing drug interactions effectively.

Mechanism Of Interaction

The theorized or clinically determined reason (i.e., mechanism) why the drug-drug interaction occurs.

Disclaimer: The information provided on this page is for informational purposes only and should not be considered medical advice. Always consult with a qualified healthcare professional regarding your specific circumstances and medical conditions.

Where Does Our Information Come From?

Information for our drug interactions is compiled from several drug compendia, including:

• Gold Standard Drug Database
• Micromedex
• Lexicomp
• DrugBank

The prescribing information for each drug, as published on DailyMED, is also used. 

Individual drug-drug interaction detail pages contain references specific to that interaction. You can click on the reference number within brackets '[]' to see what reference was utilized.

The information posted is fact-checked by HelloPharmacist clinicians and reviewed quarterly.