Levothyroxine
Absolute Contraindications
- Untreated adrenal insufficiency
- Thyrotoxicosis
Main Side Effects
- Hyperthyroid symptoms (e.g., palpitations, tremors, sweating) if overdosed
- GI upset
Main Interactions
- Iron/calcium supplements (reduce absorption; take 4 hours apart)
- Antacids (reduce absorption)
- Warfarin (may enhance anticoagulant effect)
Main Monitoring Requirements
- TSH and free T4 levels every 6-8 weeks initially, then every 6-12 months Pregnancy & Breastfeeding
- •Safe in both; dose adjustments may be required during pregnancy