Thank you for question. You are 29-years-old, and had PRP applied to your scalp with microneedling using lidocaine. After about a week, you 3-4 times the normal hair shedding. The doctor said it was likely the microneedling. You are asking if the shed is normal, when it might resolve, and if you should keep using PRP. I can certainly give you some guidance about this. I’m a Board Certified Cosmetic Surgeon and Fellowship-trained Oculoplastic Surgeon. I’ve been in practice in Manhattan and Long Island for over 20 years. I’ve been performing hair transplants since I started my practice. I’m also the founder of TrichoStem Hair Regeneration Centers, based on a system we developed that uses extracellular matrix and PRP for non-surgical treatment of pattern hair loss for men and women since 2011. We have patients from around the world who come to see us for this treatment. Microneedling can cause trauma to the scalp, resulting in hair shedding. Normally, microneedling to the scalp is not deep enough to damage hair follicles, but you should discuss this with your doctor as I’m not aware of the details and protocol of your treatment. Microneedling itself is meant as a controlled injury, with the body reacting with a wound healing response. Although microneedling does produce collagen as a wound healing response, collagen is not factor for renewed hair growth. For the scalp to respond with a renewed hair growth cycle due to microneedling is up for debate, but success with this approach is inconsistent at best. Although I have used microneedling with PRP to treat issues like acne scars, and wrinkles as they do benefit from collagen stimulation, most doctors who apply PRP alone for hair loss use an injection treatment. PRP is proven to stimulate hair growth. However, in my experience, I find that PRP only stimulates short-term hair growth, which will take several treatments to achieve, and more treatments to sustain. With PRP alone to treat hair loss, it’s difficult to get an answer from doctors for how many treatments they will need, and how long they will need treatment. I have been doing hair loss injections since 2011, and have pioneered hair loss injection treatments with our Hair Regeneration system. PRP is not the main ingredient, but rather the activator of the main ingredient extracellular matrix by ACell. With this treatment, we can get more predictable results than PRP alone, with far less treatments. For female pattern hair loss patients, over 99% see thicker hair and more hair density. For most patients, only one treatment is needed, which can last 3-5 years, often beyond. Some patients with advanced hair loss may get a second treatment at 15-24 months. Each treatment is customized based on a person’s age, age of onset of hair loss, degree of hair loss, and other hair loss medications or treatment used. There is more than one treatment or protocol available for female pattern hair loss. It is important to establish what your chosen doctor’s experience is, what results you expect to see, how many treatments it will take to achieve results, and how long the results will last. Look into other treatment protocols before considering microneedling and PRP as the only option. I hope you found this information helpful. Thank you for your question.