FELDENE (piroxicam) capsule is a nonsteroidal anti-inflammatory drug, available as maroon and blue #322 10 mg capsules and maroon #323 20 mg capsules for oral administration. The chemical name is 4-hydroxyl-2-methyl-N-2-pyridinyl-2H-1,2,-benzothiazine-3-carboxamide 1,1-dioxide. The molecular weight is 331.35. Its molecular formula is C15H13N3O4S, and it has the following chemical structure.
Piroxicam occurs as a white crystalline solid, sparingly soluble in water, dilute acid, and most organic solvents. It is slightly soluble in alcohol and in aqueous solutions. It exhibits a weakly acidic 4-hydroxy proton (pKa 5.1) and a weakly basic pyridyl nitrogen (pKa 1.8).
The inactive ingredients in FELDENE include: Blue 1, Red 3, lactose, magnesium stearate, sodium lauryl sulfate, starch.