Hair Loss: Causes, Diagnosis and Treatment

Hair loss can result from changes in the hair growth cycle, inherited pattern, inflammation, infection, pulling or nutritional problems.

Hair loss may mean extra strands on a pillow, in the shower or on a brush, or a visibly smaller ponytail. Some people notice a receding hairline, a widening part, a bald patch or less density across the scalp. The scalp can feel normal, but itching, scaling, tenderness, redness or broken hairs may accompany infection or inflammation. Hair loss can affect scalp hair, eyebrows, eyelashes or body hair. The pattern, speed and condition of the scalp help guide assessment.

Hair loss is not usually an emergency, but arrange a clinical assessment if it starts suddenly, progresses quickly, forms smooth patches, or occurs with pain, marked itch, scaling, pus or inflamed skin. Prompt review is also sensible when eyebrows or eyelashes are changing, or when shedding follows a new medicine or illness. Seek urgent care for hair loss with severe facial swelling, breathing difficulty or signs of a serious allergic reaction.

The causes below are listed alphabetically, not by likelihood. Alopecia areata presents with sharply defined patches caused by an immune reaction around follicles. Male Pattern Hair Loss and Female Pattern Hair Loss cause gradual pattern changes influenced by inherited follicle sensitivity. Nutritional Hair Loss may follow inadequate intake or an absorption problem. Postpartum Hair Loss can follow hormonal change after pregnancy. Scalp Ringworm may cause scaling, broken hairs and inflamed patches. Telogen Effluvium can shift many hairs into shedding after a physical or emotional stressor. Traction Alopecia follows repeated tension from tight styles or extensions.

A clinician asks when shedding began, whether it is patchy or diffuse, recent illness or childbirth, diet changes, medicines, family history and styling habits. They inspect the scalp and hair shafts, sometimes using magnification or a gentle pull test. Blood tests may be considered when the history suggests a nutritional, hormonal or systemic contributor. A scalp sample or fungal testing may help when infection or inflammation is suspected. Bring a list of medicines and photographs showing how the pattern has changed.

Care is matched to the finding. A clinician may treat scalp infection, correct a confirmed nutritional deficiency, reduce traction, or address an inflammatory or immune-related condition. Pattern hair loss may be managed with topical minoxidil or, for some people, finasteride treatment after a discussion of suitability and safety. PRP for hair loss may be discussed as a procedure-based option. Results and maintenance needs vary, so a diagnosis should come before choosing a product or procedure.

Use gentle handling, avoid repeatedly tight hairstyles and rotate styles that place tension on the same area. Limit harsh chemical processing and excessive heat, and detangle with care. Eat a varied diet rather than taking high-dose supplements without a reason. Treat persistent scalp scaling or itch instead of scratching. Keeping dated photographs in similar lighting can reveal gradual change and gives a clinician useful information.

Note whether you also have scalp scale, itch, soreness, redness, broken hairs, nail changes, eyebrow loss or increased facial hair. Fatigue, weight change, bowel symptoms or menstrual changes can add context for a broader health assessment. These accompanying features do not identify a cause on their own, but they can help determine which examination or tests are useful.

The linked pages explain named conditions and treatment options in more detail. A clinician can help connect your pattern of loss with the most relevant information.