Thank you for your question.PRP is the Platelet Rich Plasma derived from your own blood therefore it is all natural. Our own cells are readily identified and accepted by our bodies. These cells are not rejected and should not cause side effects. Any notable issues would be tenderness from the injection entries and a slight inflammatory reaction from an increase in circulating growth factors which can result in some temporary shock to the follicles. Also, if recent fever or illness occur, it may be best to wait up to 60 days before doing PRP to avoid any negative outcomes.It is important to consult with your surgeon about any questions or concerns you may have. They are your best resource.Best wishes in your endeavors.Sincerely,James Fernau, MD,FACS Board Certified Plastic Surgery, Member of ASPS,ISAPS,The Rhinoplasty Society, AAFPRS, OTO/HNS, ASLMS, International Federation for Adipose Theraputic & Science