The 500 mg/325 mg tablet of Mefniwel P is used to treat fever. A combination of medications called Mefniwel P 500mg/325mg Tablet is used to treat aches and pains. It prevents the brain's chemical messengers from alerting us to pain. Pain from headaches, migraines, nerve pain, toothaches, sore throats, menstruation pain, arthritis, and muscle aches can all be effectively relieved by it. To receive the best benefit, take it exactly as directed. It can be risky to take more or longer than is necessary. Generally speaking, you should take the smallest effective dose for the shortest amount of time.