--Dicyclomine: Dry mouth, blurred vision, nausea, drowsiness, weakness, nervousness, dizziness, bloating, heartburn, constipation, difficulty urinating, sensitivity to light. Mefenamic Acid: Nausea, vomiting, upset stomach, heartburn, diarrhea, constipation, drowsiness, dizziness, headache, skin rashes, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing, unexplained stiff neck, vision changes.