Usually start at twice a day, but may be able to give only once a day. Monitor T4 levels at 2-4 week intervals taking a blood sample to check the level before the daily treatment and 6 hours after the daily treatment. Side Effects None if given at correct dosage. Do not use in patients with heart disease or high blood pressure. Do not use in patients with untreated Addison's disease .
Differences exist between brands.
Do not change brands if possible. If need to change, recheck levels and adjust dose. May be safe to use in pregnancy and nursing but no studies confirm that. Drug or Food Interactions Increases effects of epinephrine, norepinephrine, and warfarin. May decrease the effect of digoxin.