Hello, I understand and appreciate your question. Brief Answer: Most likely hair lost is side effect of Levothyroxine. Detailed Answer: Common side effects of Levothyroxine include hair loss during the first few months of treatment. This effect is usually temporary. The patient suffers from hypothyroidism because he is treated with Levothyroxine The characteristic symptom of hypothyroidism is hair loss. Therefore, we may think it is a symptom indicating that it is necessary to evaluate the dose of Levothyroxine treatment. I suggest you test thyroid hormone level examination, and dose assessment by an endocrinologist. Hair loss is found in people taking Furosemide and Metoprolol. Thank you for asking your query on health care magic. If you have more questions, feel free to ask. Thank you. Kind regards.