Naproxen sodium + codeine

Naproxen sodium + codeine is a fixed-dose combination of two analgesic agents used for the relief of moderate to moderately severe pain. Naproxen sodium is a nonsteroidal anti-inflammatory drug (NSAID) that works primarily by inhibiting prostaglandin synthesis, thereby reducing inflammation, pain, and fever[5][4]. Codeine is an opioid analgesic that acts as an agonist at opioid receptors in the central nervous system to provide pain relief[6]. The combination provides additive analgesic effects from both components and may be used when monotherapy with either agent is insufficient[2]. This combination does not demonstrate synergistic interaction but rather additive efficacy and increased risk of adverse effects associated with opioids such as nausea or drowsiness[2].