Tests and diagnosis
Before making a diagnosis, your doctor will likely give you a physical exam and ask about your medical history and family history. Your clinician may also perform tests, such as the following:
Blood test
This may help uncover medical conditions related to hair loss, such as thyroid disease.
Pull test
Your doctor gently pulls several dozen hairs to see how many come out. This helps determine the stage of the hair shedding process.
Scalp biopsy
Your doctor scrapes samples from the skin or from a few hairs plucked from the scalp to examine the hair roots. This can help determine whether an infection is causing hair loss.
Light microscopy
Your doctor uses a special instrument to examine hairs trimmed at their bases. Microscopy helps uncover possible disorders of the hair shaft.