Why is ketorolac limited to short-term use?

Ketorolac is a powerful injectable and oral NSAID used for moderate to severe acute pain, but it is limited to a maximum of five days of treatment because of its high risk of serious gastrointestinal bleeding, ulceration, and perforation. Ketorolac provides pain relief comparable to moderate-dose opioids without the sedation and respiratory depression, making it valuable for postoperative and emergency department pain management. However, its potent inhibition of COX-1 prostaglandins that protect the stomach lining makes prolonged use dangerous.