If you haven't had a bowel movement in three days, you could be suffering from constipation. Constipation is sometimes treated with laxatives, but usually only on a short-term basis. Metamucil falls into the category of bulk-forming laxatives, which are safe to use for a longer period than some other types of laxatives, such as stimulant laxatives, as long as you take them with plenty of water.
Effects of Soluble Fiber
Metamucil may be able to treat your constipation in as little as 12 hours, but it can have side effects that include bloating and abdominal pain, according to the University of Maryland Medical Center. Psyllium, the main ingredient in metamucil, is a type of soluble fiber that absorbs liquid and swells, which makes your stools both larger and softer. This helps make your stools easier to pass. Limit your psyllium use to no more than seven days to reduce the risk of it becoming habit-forming, recommends Drugs.com, and take each dose with a full glass of water to help prevent choking.