Hello dear I understand your concern Drinking before and after meal has no association with the constipation. Overall drinking of water should be a 3-4 litre per day to prevent constipation. Your symptoms could be due to enteropathy (more in diabetes), fecoliths obstruction, inadequate fiber intake. hypothyroidism. The more the bowel is not emptied the more difficult it becomes to evacuate as the liquid content of the stool is reabsorbed. The stool becomes hard and this hard stuff goes on accumulating in the gut produce stomach pain. I would suggest to consult the gastroenterologist and undergo stool examination, ultrasound scan of abdomen,colonic transit studies, defecography and colonoscopy examination. Following advice will help you: Glycerine enema for immediate relief Syrup Lactulose: can be taken up to 30 ml twice a day Tab bisacodyl at bedtime can useful Bulking agents like senna Lifestyle changes: Drink one spoon of honey in warm water daily in morning before the bowel movement, Set Up regular time for the motion. Eat high fiber diet. Every meal should have salads and fruits with skin. Daily evening and morning walk for 30-45 minutes to regularize the bowel movement. Take more fruits and green leafy vegetables in the diet. Hope this may help you Contact further if follow up needed Best regards Dr. Sagar