Increased hair loss after PRP acell. When will it stop and how long will it take for the hair to regrow again?

Although relatively uncommon, shock loss after Acell is a distinct entity. It is thought to occur secondary to pressure on the hair follicles or some sort of immunologic reaction. Shock loss may take three months to dissipate and six to nine months for the hair to re-grow. Treatment with PLAIN  PRP and minoxidil is suggested to speed the process. 
Jeff Rapaport MD FAAD
Realself All-star

Though on the rare side, but not unheard of, Acell can cause an inflammatory response that will exhibit such symptoms. Though temporary and quite surprising, not to mention the disappointment, your hair should return better than before and the benefits of the treatment should be realized in a few more months. I believe you will find this to be a temporary setback.
Wishing you a wonderful outcome.
Warmly,
Arbella Sarkis, MD