What kind of shed is happening?

Hello,

The shedding you described before starting finasteride could have been due to both androgenetic alopecia (AGA) and a possible overlap with telogen effluvium (TE), as TE often accelerates hair loss in those with AGA. AGA causes gradual thinning and miniaturization of hair follicles, leading to progressive loss over time.

When you started finasteride, the shedding likely stopped because it reduced DHT levels, addressing the hormonal cause of AGA and potentially stabilizing hair loss. TE, if present, often resolves once the underlying trigger (e.g., stress, hormonal changes) is addressed.

Best regards,
Dr. Marco Barusco

AGA does not classically cause shedding. It causes miniaturization of hair shafts over time (thinning of hair shafts) and a daily (normal) hair fall rate of 100-150 hairs lost per day. These hairs overtime are replaced with thinner and finer hairs (miniaturization). AGA can effectively be treated with finasteride. In the first 6 months of finasteride use there can even be a shed phase from the medication before the thickening benefits, which often happen closer to 1 year.
If you had a positive hair pull test then that indicates TE - which has increased daily hair fall rates. TE is not "treated" - it self resolves on its own after resolution of the stress that caused the TE has been stopped. Classically, time allows it to resolve and is a reversible condition. The shedding that you noted to stop from TE is likely being incorrectly attributed to starting finasteride.