While piroxicam gel is a topical medication, piroxicam is also available as an oral prescription pain reliever in pill form. As an NSAID, piroxicam gel slows or stops the body's production of prostaglandins, the chemicals responsible for causing the inflammation of tissues.ide effects of piroxicam gel may include flu-like symptoms. Bronchial spasms and shortness of breath are side effects of piroxicam gel. Piroxicam and other non-steroidal anti-inflammatory drugs (NSAIDs) may help dull mild to moderate pain.