Probiotics are live, nonpathogenic microorganisms (usually bacteria or yeasts) marketed as dietary supplements. They have not been approved by the FDA for any indication. Since our last article on this subject, some new data have become available.

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

About 50% of the world’s population is infected with Helicobacter pylori. These gastric bacteria can cause chronic inflammation and have been associated with development of gastritis, peptic ulcer disease, gastric adenocarcinoma, and gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Eradication of H. pylori can promote gastric healing, prevent recurrence of duodenal and gastric ulcers, and reduce the incidence of gastric cancer. Guidelines for treatment of H. pylori infection were updated recently.

Web sites and blogs are advising patients that periodic "cleansing" of the colon is necessary to rid the body of toxins.

Clostridium difficile infection (CDI) is the most common infectious cause of healthcare-associated diarrhea in adults. The incidence and severity of CDI have increased in recent years with the emergence of an epidemic virulent strain (NAP1/BI/027). Common risk factors include admission to a healthcare facility, increasing age and severity of underlying illness, gastric acid suppression and exposure to antimicrobials, particularly clindamycin, ampicillin, cephalosporins or fluoroquinolones. Patients who develop CDI while receiving a precipitating antibiotic should have the antibiotic...

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).

The FDA has approved Rebyota (Ferring), a rectally-administered, live fecal microbiota suspension, for prevention of additional recurrences of Clostridioides difficile infection (CDI) following antibiotic treatment for a recurrent episode of CDI in adults. Rebyota is the first microbiome-based treatment to be approved for this indication. It is not approved for initial treatment of CDI. Fecal microbiota transplantation (FMT) has been used in patients with multiple CDI recurrences.

The gram-positive anaerobic bacillus Clostridium difficile is the most common identifiable cause of antibiotic-associated diarrhea. The antibiotics most often implicated have been ampicillin, second and third generation cephalosporins, clindamycin and fluoroquinolones. The emergence in recent years of a new, more toxic epidemic strain (BI/NAP1), possibly related to widespread use of fluoroquinolones, has caused a marked increase in the incidence and severity of C. difficile-associated disease (CDAD).

Atopic dermatitis (AD; also known as eczema) is frequently associated with other atopic disorders such as allergic rhinitis, asthma, and food allergy. It commonly presents in infancy and early childhood and has a relapsing course, often improving by adolescence, but sometimes persisting into (or first appearing in) adulthood or even old age.

The guanylate cyclase-C receptor agonist linaclotide (Linzess – Abbvie/Ironwood) was first approved by the FDA in 2012 for treatment of chronic idiopathic constipation and irritable bowel syndrome with constipation in adults. The drug has now been approved for treatment of functional constipation in patients 6-17 years old. Linaclotide is the only drug to be approved in the US for treatment of functional constipation.