Check with your doctor who will usually order thyroid tests and a barium enema to rule out obstruction. Most of the time, these tests will be normal and you suffer from a faulty diet. The pain of constipation is usually caused by gas stretching your colon where it has been blocked by hard stool. Food is turned into a soup in your stomach and remains that way until it reaches your colon, where water is absorbed and stool is formed. If you don't drink enough fluid or eat enough fiber, the stool rapidly turns into hard pieces that are difficult to pass. Low-fiber foods, such as breads, rolls, pastries, bagels, pretzels, noodles and pasta cause hard stools, while eating fiber-rich foods, such as fruits, vegetables, whole grains and beans, keep everything soft.
If you drink lots of water and eat lots of fiber and are still constipated, you may have nerve damage and need to be checked for diabetes or other causes. Laxatives and fiber supplements offer little help, but your doctor may prescribe other drugs, such as the antibiotic, erythromycin; the gout medicine, colchicine; or the stomach medicine, Prevacid, which may be helpful in some cases of chronic constipation.