Constipation, Laxatives, and You

Laxatives have a bad name in our popular culture, as something used in pranks or designed to be used only in extreme circumstances. However, what you don’t know about laxatives just might be preventing you from feeling better every day.

Constipation is an extremely common problem. We know at least 7% of American adults have significant recurrent constipation. We estimate that the real numbers are closer to 30-40%, and that most of us just don’t know it! We define it with the “Rome Criteria,” a set of guidelines for gastrointestinal disorders, and the definition actually covers a lot of people. If you have two or more of the following, you are, in fact, also constipated.

  1. Less than three bowel movements per week
  2. At least one episode of incontinence per week
  3. Painful, lumpy, or hard bowel movements
  4. Large diameter stools

Constipation is insidious because it can be chronic and it sustains itself. The colon’s job is to hold stool and reabsorb water. If at any point stool sits too long, it becomes hard and dense as the water reabsorbs. In addition, you know you have to go because your colon stretches. However, you can ignore that signal, and for individuals who are constipated, their colon gets more and more stretched out, meaning you don’t even feel like you need to go until you have a large amount of waste to get rid of.

So how do we fix this? Laxatives. Improving your diet with fiber and increased water intake will only go so far, and usually is better for prevention than for treatment of constipation. Instead we recommend varying types of laxatives, which have varying types of side effects.

Our mainstay is Miralax. Miralax and its cousins are a chemically inert, non-absorbed powder which you mix into a beverage. It is of a class called “osmotic laxatives,” meaning that the powder holds water in the intestine, keeping everything hydrated and soft. It is mainly side effect free, although does have some associated bloating for some people, with the worst problem being that if you take too much, you may get diarrhea. It takes about 6 hours to work, and works best if drank quickly. Other laxatives in this class include magnesium citrate, milk of magnesia, and lactulose. These should be the baseline of any attempt to solve your constipation, and it should be kept in mind that you should stay on these for quite some time, to give your colon time to unstretch.

Stimulant laxatives work by triggering the colon itself to move. They don’t soften stool, but encourage you to have a bowel movement. These are the ones that work a bit more like the movie version, where they can cause some cramping and the urge to go emergently if too much is taken. However, they often work really well in conjunction with an osmotic laxative. Examples include dulcolax or senna (aka, Ex-Lax).

In the worst case scenarios, there are some new prescription treatments (Linzess and Amitiza) which work by increasing the amount of fluid your intestines secrete, thus keeping stool hydrated and soft. If basic measures are not working for you, discuss further options with your physician.