They should be used in moderation just as all laxatives should be. For instance, some peoples' colon works just fine but they can't expel the stool due to incoordination of the pelvic muscles and the rectum. In these cases biofeedback therapy is fast and effective. A special X-ray called a defogram can often show these abnormalities. Even diseases such as multiple sclerosis, scleroderma, etc. can be treated.
Drugs are often the culprit and can be changed.
If these medications cannot be stopped then the above treatments are usually effective. The field of gastrointestinal motility is progressing rapidly. We are coming to understand how nerves and muscle cells talk to each other to control how things move through the GI tract. Several new drugs will be released soon that work specifically on the colon muscles and nerves to increase stool frequency. Future research will certainly lead to better therapy with fewer side effects.