People sometimes use mineral oil to help relieve constipation. It helps by covering the stool with a waterproof coating so it stays moist and is easier to pass. Although side effects aren't common and the oil tends to be effective, mineral oil can sometimes cause serious side effects, so don't use mineral oil without first consulting your doctor to make sure it is safe for you.
The most common side effects associated with mineral oil are gastrointestinal in nature, including stomach cramps, diarrhea, nausea and gas. More severe reactions that warrant seeking immediate medical attention include rectal bleeding or failure to have a bowel movement within eight hours of taking mineral oil.
Other Side Effects
Mineral oil may also cause severe allergic reactions, including hives, rash, swelling and trouble breathing. Other potential side effects include dizziness, fainting, weakness, irritation, swelling, muscle cramps and pain. Seek medical attention if you experience any of these side effects.
Other Potential Risks
It's also possible for people to accidentally inhale, or aspirate, mineral oil when they are swallowing it. This sometimes occurs in children and can cause dangerous effects, including respiratory distress and pneumonia, according to an article published in Paediatrics & Child Health in March 2001. Don't take mineral oil within two hours of eating, or the mineral oil may decrease the absorption of some nutrients and interfere with the digestive process, according to the National Multiple Sclerosis Society. Prolonged use of laxatives, such as mineral oil, may cause the loss of normal bowel function, so don't use mineral oil for longer than a week unless your doctor tells you to do so.
Don't use mineral oil if you have a blockage in your intestines, have appendicitis or are bedridden. Don't take other medications within two hours of using mineral oil, or it may interfere with the effectiveness of your medications. In addition, avoid taking mineral oil if you're pregnant -- if you use it for a long time during pregnancy, it can cause your newborn to experience severe bleeding, according to Drugs.com.