Adverse reactions associated with levothyroxine sodium tablets therapy are primarily those of hyperthyroidism due to therapeutic overdosage
[see Warnings and Precautions (5), Overdosage (10)].They include the following:
General:fatigue, increased appetite, weight loss, heat intolerance, fever, excessive sweating
Central nervous system:headache, hyperactivity, nervousness, anxiety, irritability, emotional lability, insomnia
Musculoskeletal:tremors, muscle weakness, muscle spasm
Cardiovascular:palpitations, tachycardia, arrhythmias, increased pulse and blood pressure, heart failure, angina, myocardial infarction, cardiac arrest
Gastrointestinal:diarrhea, vomiting, abdominal cramps, elevations in liver function tests
Dermatologic:hair loss, flushing, rash
Endocrine:decreased bone mineral density
Reproductive:menstrual irregularities, impaired fertility
Seizures have been reported rarely with the institution of levothyroxine therapy.
Spl unclassified section
Hypersensitivity reactions to inactive ingredients have occurred in patients treated with thyroid hormone products. These include urticaria, pruritus, skin rash, flushing, angioedema, various gastrointestinal symptoms (abdominal pain, nausea, vomiting and diarrhea), fever, arthralgia, serum sickness and wheezing. Hypersensitivity to levothyroxine itself is not known to occur.