Irritable Bowel Syndrome Drug Linzess, What You Should Know
It’s been more than six years since there has been a drug approved for treatment of irritable bowel syndrome with constipation (IBS-C) or chronic idiopathic constipation (CIC). Now with the Food and Drug Administration’s (FDA) approval of Linzess (linoclotide), that has changed, but what should you know about this medication?
Do you have irritable bowel syndrome with constipation?
If you answered “yes” to this question, you are among the estimated 13 million people in the United States with this chronic condition that can have a serious impact on your daily life. Individuals who have irritable bowel syndrome with constipation typically experience constipation, hard or lumpy stools more than one-quarter of the time, loose stools less than one-quarter of the time, and abdominal pain.
Nearly three times as many people in the United States experience chronic idiopathic constipation, which is defined as having fewer than three bowel movements per week for three months or longer. Individuals typically need to strain at least one-quarter of the time and also can experience abdominal discomfort and bloating. As the name implies, the cause is unknown, not due to any overt disease or injury.
While occasional constipation can often be treated effectively with a mild over-the-counter laxative, people who suffer with IBS-C or CIC often find they must turn to laxatives more regularly or get a prescription, although not much is available (see below). Linzess differs from the other FDA-approved medication for these conditions because it is a guanylate cyclase-C agonist.
How Linzess works
Based on the results of clinical trials, experts believe Linzess works by attaching to the guanylate cyclase-C receptors in the intestinal tract, which then triggers an increase in the secretion of fluid. This action improves the movement of stool and also helps reduce abdominal pain.
More than 2,800 adults participated in the Phase III trials of Linzess, and the overall results showed that:
- Abdominal pain relief was experienced by patients during the first week of treatment and sustained throughout the 12-week treatment cycle, although the maximum benefit occurred at weeks 6 through 9
- The best relief from constipation occurred during the second week of treatment
- Patients who switched to a placebo during the trials said their pretreatment symptoms returned within seven days
- The recommended doses are 290 micrograms for people with IBS-C and 145 micrograms for people with CIC
Some other things you should know about Linzess:
- Dosing is once daily and should be taken at least 30 minutes before the first meal of the day
- Linzess should not be taken by anyone younger than 18 years old. Although no studies have been done in children, animal studies showed that an adult dose of linoclotide caused the deaths of young mice.
- The most common side effect of Linzess is diarrhea. Other reactions may include gas, abdominal bloating, and abdominal pain. Linzess should not be used by anyone who has intestinal blockage.
Other treatments for IBS-C and CIC
Lifestyle modifications are recommended for people who suffer with IBS-C or CIC. A gradual increase in the amount of fiber in the diet, mainly through fresh fruits and vegetables, legumes, and whole grains, is suggested, along with adequate fluids. Regular physical exercise, bowel habit training, and stress management also can be helpful in alleviating symptoms, but not everyone responds adequately to these steps.
Less often, treatments such as biofeedback, behavior therapy, and electrical stimulation have been used with varying success. For some patients, these measures can be an effective complement to other treatments.
The other FDA-approved medication for IBS-C and CIC is lubiprostone (Amitiza), an oral drug typically taken twice daily. Amitiza is known as a selective chloride channel activator. This means it increases secretion of chloride, which in turn increases fluid in the gut and helps move stool through the intestinal tract. Common side effects include nausea, diarrhea, gas, vomiting, dry mouth, runny nose, cough, fever, and headache.
Tegaserod (Zelnorm) was approved by the FDA for treatment of IBS in women. However, in 2007 the FDA asked Novartis (maker of Zelnorm) to suspend sales and marketing of the drug because it demonstrated a higher risk of stroke, heart attack, and unstable angina compared with placebo.
Individuals who suffer with these constipation disorders should consult their healthcare professional about all possible treatments for their condition. The introduction of Linzess to the marketplace for treatment of irritable bowel syndrome with constipation and chronic idiopathic constipation offers patients one more option.