What causes hair loss?
Hair loss has hormonal, nutritional, autoimmune, medication-related, and stress-related causes. Workup typically includes DHT, thyroid status, iron studies, vitamin D, and B12.
Full answer
Hair loss patterns differ by cause. Androgenetic alopecia is the most common pattern in both sexes and is DHT-mediated. Telogen effluvium is a diffuse shedding pattern triggered by stress, illness, weight change, postpartum hormonal shift, or thyroid dysfunction. Alopecia areata is autoimmune. Within oMeds review, the workup includes DHT, total/free testosterone, SHBG, TSH, free T4, ferritin, iron, vitamin D, vitamin B12, and a basic CBC. Treatment selection depends on diagnosis; pharmacologic options are provider-reviewed.
Educational. Not a substitute for individualized provider review.
- Hair Restoration pathway — Primary source · oMeds
- Reviewed by Dr. Laura Purdy, MD, MBA · Clinical Director, oMeds · Last reviewed 2026-05-29