Side 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.Piroxicam gel is commonly used to treat painful inflammation caused by arthritis.Minor stomach discomfort is a possible side effect of piroxicam gel, although severe stomach pain could indicate a complication that requires emergency medical attention.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.