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.
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