Minor side effects of Metamucil include bloating, gas and stomach cramping, according to WebMD. Everyday Health explains people may also experience a minor change in bowel habits. WebMD reveals that more serious side effects include an allergic reaction, dizziness, chest pain, vomiting and trouble breathing. Patients who experience serious side effects should stop using Metamucil at once and consult a doctor.
Everyday Health notes that other serious side effects include constipation that lasts more than seven days, an itchy skin rash and rectal bleeding. Symptoms of an allergic reaction to this medication denote hives, difficulty breathing, and swelling of the face, lips, tongue, mouth or throat.
Metamucil should be taken with at least 8 ounces of water so the powdery substance does not swell in the throat and cause choking, according to WebMD. Metamucil, with the active ingredient psyllium, comes in wafer, powder and capsule form, according to Drugs.com.
Psyllium is a fiber laxative that treats constipation. The substance absorbs liquid in the intestines and creates a bulky stool that passes more easily through the gastrointestinal tract, according to MedlinePlus. The medicine can be taken up to three times daily by mixing the powder or granules with a full glass of water or chewing the wafers thoroughly and chasing them with at least 8 ounces of water. Individuals shouldn't take this medicine for more than seven days.