Although different NSAIDs have different structures, they all work by blocking cyclo-oxygenase (COX) enzymes. There are two main types of COX enzymes: COX-1 and COX-2. Both types produce prostaglandins; however, the main function of COX-1 enzymes is to produce baseline levels of prostaglandins that activate platelets and protect the lining of the gastrointestinal tract, whereas COX-2 enzymes are responsible for releasing prostaglandins after infection or injury. Prostaglandins have a number of different effects, one of which is to regulate inflammation.
Pain recurrence was reported by only three studies which could not be pooled: a higher proportion of patients treated with 75 mg diclofenac (IM) showed pain recurrence in the first 24 hours of follow-up compared to those treated with 40 mg piroxicam (IM) (60 participants: RR , 95% CI to ); no significant difference in pain recurrence at 72 hours was observed between piroxicam plus phloroglucinol and piroxicam plus placebo groups (253 participants: RR , 95% CI ); and there was no significant difference in pain recurrence within 72 hours of discharge between IM piroxicam and IV paracetamol (82 participants: RR , 95% CI to ).
Treatment of endometriosis can be with medication or surgery.