Agent |
Some Side Effects |
Comments |
Bulking agents (fiber)* |
||
Bran |
Bloating, passing of gas (flatulence), and poor absorption of iron and calcium |
Bulking agents generally are used to prevent or control chronic constipation. |
Polycarbophil |
Bloating and flatulence |
|
Methylcellulose |
Less bloating than with other fiber agents |
|
Psyllium |
Bloating and flatulence |
|
Stool softeners |
||
Docusate |
— |
Stool softeners may be used to treat constipation and are often used to help prevent it. Docusate is not effective for severe constipation. |
Glycerin |
Rectal irritation |
|
Mineral oil |
Lung inflammation caused by fats in the lungs (lipid pneumonia), poor absorption of fat-soluble vitamins, dehydration, and loss of control over bowel movements (fecal incontinence) |
|
Osmotic agents |
||
Lactulose |
Abdominal cramps and flatulence |
Osmotic agents are better for treating constipation than for preventing it. |
Magnesium salts (magnesium hydroxide and magnesium citrate) |
Too much magnesium in the body (magnesium toxicity), dehydration, abdominal cramps, and fecal incontinence |
|
Polyethylene glycol |
Fecal incontinence (related to dosage) |
|
Sodium phosphate |
Rare cases of sudden kidney failure |
|
Sorbitol |
Abdominal cramps and flatulence |
|
Stimulant laxatives |
||
Anthraquinones (found in senna, cascara, and castor oil) |
Abdominal cramps and dehydration |
Stimulant laxatives are not used if there is a possibility of an intestinal obstruction. Prolonged use can damage the large intestine. Lubiprostone can be used for chronic constipation. It is available for long-term use. |
Bisacodyl |
Fecal incontinence, a low level of potassium in the blood (hypokalemia), abdominal cramps, and rectal burning with daily use of the suppository form |
|
Linaclotide |
Abdominal cramps, flatulence Not used in children |
|
Lubiprostone† |
Nausea, particularly when the drug is taken on an empty stomach |
|
Enemas |
||
Mineral oil or olive oil retention |
Fecal incontinence |
Although rare, giving an enema can injure the rectum if the procedure is done roughly. |
Tap water |
Fluid overload if a lot of water is absorbed |
|
Phosphate |
A high level of phosphate in the blood (hyperphosphatemia) |
|
Soapsuds |
Cramps |
|
*The dose of fiber supplements should be gradually increased over several weeks to the recommended dose. |
||
†Lubiprostone and linaclotide are available only by prescription. |