11 DESCRIPTION
DAYPRO (oxaprozin) caplet is a nonsteroidal anti-inflammatory drug, available as caplets of 600 mg for oral administration. The chemical name is 4,5-diphenyl-2-oxazole-propionic acid. The molecular weight is 293. Its molecular formula is C18H15NO3, and it has the following chemical structure.

Oxaprozin is a white to off-white powder with a slight odor and a melting point of 162°C to 163°C. It is slightly soluble in alcohol and insoluble in water, with an octanol/water partition coefficient of 4.8 at physiologic pH (7.4). The pKa in water is 4.3.
The inactive ingredients in DAYPRO include: microcrystalline cellulose, hypromellose, methylcellulose, magnesium stearate, polacrilin potassium, starch, polyethylene glycol and titanium dioxide. DAYPRO 600-mg caplets are white, capsule-shaped, scored, film-coated, with DAYPRO debossed on one side and 1381 on the other side.