Hyperthyroidism and hair loss

Hair may shed more noticeably during washing or brushing, with thinning spread across the scalp rather than a single sharply defined bald patch. Hair can also feel finer or more fragile. Thyroid-related shedding may appear after other symptoms have started, and growth usually depends on bringing thyroid hormone activity back into its target range. Hair loss can have other explanations, including nutritional problems, medication effects, scalp conditions, or another pattern of hair loss, so the symptom alone does not identify the cause.

Arrange a medical assessment if shedding is new, persistent, or accompanied by weight change, tremor, heat intolerance, sweating, anxiety, or a racing heartbeat. A clinician may examine your scalp and request thyroid blood tests alongside other tests guided by your history. Take prescribed thyroid treatment exactly as directed, and do not stop it because hair shedding changes. Use gentle hair care, avoid tight styles and harsh chemical treatments, and mention supplements before starting them. You can read about [Hyperthyroidism](/conditions/hyperthyroidism/) and related symptoms such as [Excessive Sweating](/symptoms/excessive-sweating/) or [Palpitations](/symptoms/palpitations/).

Seek urgent help for hair loss with severe weakness, confusion, fainting, chest pain, marked breathlessness, or a very fast or irregular heartbeat. Contact a clinician soon if shedding is sudden, forms smooth patches, affects the eyebrows, or comes with scalp pain, scaling, or sores. Those features may point to a problem needing a separate assessment rather than thyroid-related diffuse shedding.

Could my thyroid levels explain this pattern of shedding? Which blood tests or scalp findings would clarify the cause? How should I care for my hair while treatment is adjusted? When should persistent thinning be reviewed by a dermatologist?