Hi Dear, Welcome to HCM. Understanding your concern. As per your query you have symptoms of abdominal tenderness while having psoriasis . Well there can be many reasons for symptoms you mention in query like inadequate fibers in diet, consuming foods known to cause gas in some people, such as milk products that contain lactose, broccoli , crohn’s disease , appendicitis , gastroenteritis , irritable bowel syndrome or urinary tract infection. I would suggest you to avoid above mentioned foods , eat light and non spicy specially at night , take light walk after every meal , eat small and frequent meals .If condition doesn t get well then consult gastroenterologist for proper examination . Doctor may order ultrasound , endoscopy along with stool test . Doctor may prescribe ornidazole , omeprazole , laxative , anti inflammatory along with antacids . I usually recommend medicine like antihistamnics like levocetirizin ans steroid . If condition doesn t get well then consult dermatologist . Hope your concern has been resolved. Get Well Soon. Best Wishes, Dr. Harry Maheshwari