Abstract
Platelet-rich plasma (PRP) is an autologous blood product containing concentrated platelets, growth factors, and anti-inflammatory cytokines that promote healing and regeneration. Platelets release active components through a degranulation process, which is inhibited by certain nonsteroidal anti-inflammatory drugs (NSAIDs). Current deferral guidelines are not established, but NSAIDs are expected to have a time-dose relationship with platelet inhibition. This article aims to review the literature regarding NSAIDs that inhibit a key enzyme in clotting, cyclooxygenase-1 (COX-1), and their effects on bulk platelet aggregation to establish guidelines for deferral times before PRP injections. After searching the literature, 25 studies met the inclusion criteria for this review. Our analysis of the data revealed several significant findings. Naproxen demonstrated inhibition of platelet aggregation lasting at least 24 hours, with possible inhibition even at 48 hours. Studies using indomethacin found recovery by 24 hours, although no other time points were measured. Ibuprofen and diclofenac inhibit platelet aggregation for 6-12 hours, depending on dose. Acetaminophen, a mild inhibitor of COX-1, does not require deferral. These results reinforce the need to defer NSAIDs with COX-1 activity before PRP injections. This review will allow for the creation of deferral guidelines that differentiate NSAIDs based on their length of platelet inhibition.