Annoxen-S Mechanism of Action

Pharmacology: Pharmacodynamics: Naproxen is a non-steroidal anti-inflammatory drugs (NSAIDs), a propionic acid derivative, with anti-inflammatory, analgesic, and antipyretic effects. The onset of pain relief is more rapid with Naproxen sodium than Naproxen therefore Naproxen sodium is recommended for the management of acute painful conditions. It inhibits synthesis of prostaglandins as with other similar agents. Naproxen reversibly inhibits yclooxygenase-1 and 2 (COX-1 and 2) enzymes, which results in decreased formation of prostaglandin precursors; has anti-pyretic, analgesic, and anti-inflammatory properties.
Pharmacokinetics: Oral bioavailability of Naproxen is 95%. Peak plasma concentrations of the Naproxen occur in 1-2 hours following oral administration of Naproxen sodium tablet. Onset of pain relief occurs within 30 minutes in patients receiving Naproxen sodium tablet. Duration of action is 7-12 hours. It is more than 99% bound to plasma protein. Naproxen diffuses into synovial fluid; it crosses the placenta and is distributed into breast milk in small amounts. The plasma elimination half-life is about 12 to 17 hours.
Naproxen is metabolized by liver. About 95% of a dose is excreted in urine as Naproxen (less than 1%) and 6-desmethylnaproxen (less than 1%) and their conjugates (66-92%). Less than 3% of a dose appears in the feces.