The FDA has approved lubiprostone (Amitiza - Sucampo/Takeda), a chloride channel activator, for treatment of chronic idiopathic constipation in adults. The only other prescription drug approved by the FDA for this indication (in 2004 for adults <= 65 years old) is tegaserod (Zelnorm), a partial agonist of serotonin that is also approved for constipation-predominant irritable bowel syndrome in women. Of course, numerous over-the-counter products are available for treatment of constipation.

The FDA has approved use of lubiprostone (Amitiza) for treatment of opioid-induced constipation in adults with chronic non-cancer pain. The drug was previously approved for chronic idiopathic constipation and irritable bowel syndrome with constipation.

Lubiprostone (Amitiza), which was previously approved for treatment of chronic idiopathic constipation in adults, has now also been approved in a lower dose for use in women with irritable bowel syndrome with constipation (IBS-C). Since tegaserod (Zelnorm) has been withdrawn from the market,2 lubiprostone is the only drug approved by the FDA for treatment of this common condition.

Linaclotide (lin´´ a kloe´ tide; Linzess – Ironwood/Forest), a guanylate cyclase-C receptor agonist, was recently approved by the FDA for oral treatment of chronic idiopathic constipation (CIC) and irritable bowel syndrome with constipation (IBS-C) in adults. It is the second drug approved for this indication; lubiprostone (Amitiza), a metabolite of prostaglandin E1, was the first.

The FDA has approved plecanatide (Trulance – Synergy), a guanylate cyclase-C receptor agonist, for treatment of chronic idiopathic constipation (CIC) in adults. Linaclotide (Linzess), another guanylate cyclase-C receptor agonist, and lubiprostone (Amitiza), a chloride channel activator, were approved earlier for treatment of CIC in adults.

The FDA has approved the opioid receptor antagonist naldemedine (Symproic – Shionogi) for treatment of opioid-induced constipation (OIC) in adults with chronic noncancer pain. Naldemedine is the third oral peripherally-acting mu-opioid receptor antagonist (PAMORA) to be approved for this indication; naloxegol (Movantik) and methylnaltrexone (Relistor) were approved earlier.

The FDA has approved naloxegol (Movantik – AstraZeneca), a pegylated derivative of the opioid antagonist naloxone, for oral treatment of opioid-induced constipation in adults with chronic noncancer pain. It is the only oral opioid antagonist approved for this indication in the US.

View the Comparison Chart: Some Drugs for Irritable Bowel Syndrome with Constipation (IBS-C)

Irritable bowel syndrome (IBS) is a common disorder characterized by recurrent abdominal pain and altered bowel habits, often accompanied by bloating. IBS is classified by its predominant bowel symptom: constipation (IBS-C), diarrhea (IBS-D), mixed type (IBS-M), or unclassified (IBS-U). Since the exact cause of IBS is unknown, the goal of treatment is symptom control. Some over-the-counter (OTC) products and prescription drugs for IBS are listed in Tables 1-4. The safety of these drugs during pregnancy and lactation is described in Table 5 (online only).

View Figure: Treatments for Irritable Bowel Syndrome (IBS) in Adults