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Hypothyroidism dose timing — GPhC CRA MCQ

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HardEndocrine TherapeuticsHypothyroidism dose timingGPhC CRA

A patient takes levothyroxine, ferrous sulfate and omeprazole. Breakfast is at 07:00 and the patient can reliably take medicines at 06:00 and 11:00. Which schedule best protects levothyroxine absorption and monitoring?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: E — Take levothyroxine at 06:00, iron at 11:00, and monitor if control changes

Iron reduces levothyroxine absorption and the authorised information advises separation by four to five hours. A consistent empty-stomach levothyroxine dose at 06:00 followed by iron at 11:00 meets that interval. Proton-pump inhibitors can also reduce absorption by increasing gastric pH, so thyroid function should be monitored if control changes rather than assuming symptom stability proves adequate exposure.

Reference: Levothyroxine 100 microgram tablets SmPC: https://www.medicines.org.uk/emc/product/5682/smpc