If a patient on thyroid hormone replacement therapy has fluctuating levels of thyroid-stimulating hormone, advise him or her to take thyroid medication with distilled water. The minerals in tap and bottled water can deactivate some of the thyroid hormone.

Since the mineral level in the water varies, so will the amount of thyroid hormone the patient receives. Some patients are especially sensitive to these small fluctuations and do much better when taking medication with distilled water. As always, remind your patient to take thyroid medication on an empty stomach and at least four hours before or after taking any mineral (e.g., calcium) supplements. — Melissa Donais, FNP, North Reading, Mass. (169-5)

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