Other names (S): 1,2,3-glycerol, glycerol
How does it function?
Glycerin draws water into the intestines, softening stool and relieving constipation.
In the blood, it attracts water, making it stay in the body longer. This may help athletes exercise longer.
Purpose and effectiveness
- Constipation. Glycerin can be injected into the rectum as a suppository or enema to reduce constipation.
- Sports performance. There is evidence that taking glycerin and water by mouth helps keep the body hydrated longer. The increase in fluid in the body may help people move a few minutes longer, and possibly move faster, especially in hot weather.
- Dandruff. Use a shampoo containing glycerin, stearic acid and sunflower oil three times a week to reduce dandruff and moisturize your scalp.
- Dry skin. Applying products containing glycerin and paraffin to the skin can reduce scaly thickness and itching in people with xerosis.
- A genetic skin disorder that causes dry, scaly skin (ichthyosis). Applying a specific prescription product containing glycerin and paraffin (Dexeryl, Pierre Fabre Laboratoires) to the skin can reduce symptoms such as itching and scaling in children with ichthyosis.
May be invalid
- Swelling (inflammation) of the membranes that protect the brain and spinal cord (meningitis). Taking glycerin and drugs used to treat meningitis does not reduce the chance of death, seizures, or damage to the stomach and intestines. But it may reduce the chance of deafness in children who survive the infection.
- Growth and development of premature infants. Glycerin is injected into the rectum as a suppository or enema and is sometimes used in premature babies to help them have bowel movements. It is thought this will help them start eating by mouth earlier. But glycerol doesn't seem to offer much benefit for this purpose.
- Stroke. Receiving intravenous (IV) glycerin from a health care professional does not improve symptoms after stroke.
Insufficient evidence
- Obesity. Early research in adults on a low-calorie diet shows that taking glycerin before meals does not increase weight loss.
- Swimmer's ear (otitis externa). Early research suggests that having your doctor place gauze soaked in fish oil phenol and glycerin into the ear canal can reduce pain and swelling as much as prescription ear drops.
- Wrinkled skin.
- Other conditions.
Side effects
When taken by mouth: Glycerin is probably safe when taken by mouth for short periods of time. Glycerin can cause side effects including headache, dizziness, bloating, nausea, vomiting, thirst, and diarrhea.
When applied to skin: Glycerin is "lovely and safe" when applied to skin. When applied to the skin, glycerin may cause redness, itching, and burning.
When administered in the rectum: Glycerin is LIKELY SAFE when inserted into the rectum.
When given through a vein: Glycerin may be unsafe when given through a vein. This can damage red blood cells.
When applied to skin: Glycerin is "lovely and safe" when applied to skin. When applied to the skin, glycerin may cause redness, itching, and burning.
When administered in the rectum: Glycerin is LIKELY SAFE when inserted into the rectum.
When given through a vein: Glycerin may be unsafe when given through a vein. This can damage red blood cells.
Special Precautions and Warnings
Pregnancy and Breastfeeding: There is not enough reliable information to know whether glycerin is safe to use during pregnancy or breastfeeding. Stay safe and avoid using.
Children: Glycerin is lovely and safe when inserted into the rectum or applied to the skin of children at least 1 month old. Oral glycerin may besafefor short-term use in children 2 months to 16 years of age.
Children: Glycerin is lovely and safe when inserted into the rectum or applied to the skin of children at least 1 month old. Oral glycerin may besafefor short-term use in children 2 months to 16 years of age.