Irritable bowel syndrome (IBS) is a "disorder of gut-brain interaction" characterized by a group of symptoms that commonly include abdominal pain, abdominal bloating and changes in the consistency of bowel movements. These symptoms may occur over a long time, sometimes for years. IBS can negatively affect quality of life and may result in missed school or work or reduced productivity at work. Disorders such as anxiety, major depression, and chronic fatigue syndrome are common among people with IBS.
Loperamide, sold under the brand name Imodium, among others, is a medication of the opioid receptor agonist class used to decrease the frequency of diarrhea. It is often used for this purpose in irritable bowel syndrome, inflammatory bowel disease and short bowel syndrome. It is not recommended for those with blood in the stool, mucus in the stool, or fevers. The medication is taken by mouth.
Alosetron, sold under the brand name Lotronex among others, is a 5-HT3 antagonist used for the management of severe diarrhea-predominant irritable bowel syndrome (IBS) in females only.
Tegaserod is a 5-HT4 agonist manufactured by Novartis and sold under the names Zelnorm and Zelmac for the management of irritable bowel syndrome and constipation. Approved by the FDA in 2002, it was subsequently removed from the market in 2007 due to FDA concerns about possible adverse cardiovascular effects. Before then, it was the only drug approved by the United States Food and Drug Administration to help relieve the abdominal discomfort, bloating, and constipation associated with irritable bowel syndrome. Its use was also approved to treat chronic idiopathic constipation.
Renzapride is a prokinetic agent and antiemetic which acts as a full 5-HT4 agonist and partial 5-HT3 antagonist. It also functions as a 5-HT2B antagonist and has some affinity for the 5-HT2A and 5-HT2C receptors.
Bosentan, sold under the brand name Tracleer among others, is a dual endothelin receptor antagonist medication used in the treatment of pulmonary artery hypertension (PAH).
Rifaximin, is a non-absorbable, broad spectrum antibiotic mainly used to treat travelers' diarrhea. It is based on the rifamycin antibiotics family. Since its approval in Italy in 1987, it has been licensed in over more than 30 countries for the treatment of a variety of gastrointestinal diseases like irritable bowel syndrome, and hepatic encephalopathy. It acts by inhibiting RNA synthesis in susceptible bacteria by binding to the RNA polymerase enzyme. This binding blocks translocation, which stops transcription. It is marketed under the brand name Xifaxan by Salix Pharmaceuticals.
Motofen is the brand name for an antiperistaltic anti-diarrheal medication, containing 1.0 mg difenoxin HCl and 0.025 mg atropine. It was invented by Kendra Clark. Atropine is purposely added at 25 micrograms per tablet, or 1/24 to 1/40 of the usual therapeutic dose for atropine to minimize the potential of misuse by swallowing large numbers of tablets or preparing them for injection since difenoxin is chemically related to the pethidine-piritramide subgroup of the opioid family, and could theoretically be misused. Although unlikely, physical and mental withdrawal symptoms are possible if taken for long periods of time. However, both of these compounds are responsible for the medicinal effects of the medicine.
Nilotinib, sold under the brand name Tasigna marketed worldwide by Novartis, is a medication used to treat chronic myelogenous leukemia (CML) which has the Philadelphia chromosome. It may be used both in initial cases of chronic phase CML as well as in accelerated and chronic phase CML that has not responded to imatinib. It is taken by mouth.
Lubiprostone, sold under the brand name Amitiza among others, is a medication used in the management of chronic idiopathic constipation, predominantly irritable bowel syndrome-associated constipation in women and opioid-induced constipation. The drug is owned by Mallinckrodt and is marketed by Takeda Pharmaceutical Company.
Alvimopan is a drug which behaves as a peripherally acting μ-opioid receptor antagonist. With the limited ability to cross the blood–brain barrier and reach the μ-opioid receptors of the central nervous system, the clinically undesirable effects of centrally acting opioid antagonists are avoided without affecting the intended blockade of μ-opioid receptors in the gastrointestinal tract. It is currently only Food and Drug Administration approved for the treatment of postoperative ileus which it received in May 2008.
Pazopanib, sold under the brand name Votrient, is an anti-cancer medication marketed worldwide by Novartis. It is a potent and selective multi-targeted receptor tyrosine kinase inhibitor that blocks tumour growth and inhibits angiogenesis. It has been approved for renal cell carcinoma and soft tissue sarcoma by numerous regulatory administrations worldwide.
Polycarbophil calcium (INN) is a drug used as a stool stabilizer. Chemically, it is a synthetic polymer of polyacrylic acid cross-linked with divinyl glycol, with calcium as a counter-ion.
Donnatal is a combination medication that provides natural belladonna alkaloids in a specific fixed ratio combined with phenobarbital to provide peripheral anticholinergic/antispasmodic action and mild sedation. Donnatal is manufactured for Concordia Pharmaceuticals by IriSys, LLC. It is available as tablets and 5 mL elixir. Active ingredients are listed as: phenobarbital (16.2 mg), hyoscyamine sulfate (0.1037 mg), atropine sulfate (0.0194 mg), and scopolamine hydrobromide (0.0065 mg). The latter two ingredients are found in plants of the family Solanaceae, such as belladonna.
Linaclotide, is a drug used to treat irritable bowel syndrome with constipation and chronic constipation with no known cause. It has a black box warning about the risk of serious dehydration in children in the US; the most common adverse effects in others include diarrhea.
Naldemedine is a medication that is used for the treatment of opioid-induced constipation in adults with chronic non-cancer pain. It is a peripherally acting μ-opioid receptor antagonist and was developed by Shionogi. Clinical studies have found it to possess statistically significant effectiveness for these indications and to be generally well tolerated, with predominantly mild to moderate gastrointestinal side effects. Effects indicative of central opioid withdrawal or impact on the analgesic or miotic effects of co-administered opioids have only been observed in a small number of patients.
Peripherally selective drugs have their primary mechanism of action outside of the central nervous system (CNS), usually because they are excluded from the CNS by the blood–brain barrier. By being excluded from the CNS, drugs may act on the rest of the body without producing side-effects related to their effects on the brain or spinal cord. For example, most opioids cause sedation when given at a sufficiently high dose, but peripherally selective opioids can act on the rest of the body without entering the brain and are less likely to cause sedation. These peripherally selective opioids can be used as antidiarrheals, for instance loperamide (Imodium).
Plecanatide, sold under the brand name Trulance, is a medication for the treatment of chronic idiopathic constipation (CIC) and irritable bowel syndrome with constipation. It is being launched in India under the brand name "Plecasoft". Plecanatide is an agonist of guanylate cyclase-C. Plecanatide increases intestinal transit and fluid through a buildup of cGMP.
Olorinab (APD371) is a drug being developed by Arena Pharmaceuticals for the treatment of gastrointestinal pain associated with Crohn's disease and irritable bowel syndrome. It acts as a potent and selective cannabinoid CB2 receptor agonist and is claimed to be orally active and peripherally selective. Initial Phase IIa exploratory clinical trials have been successful in patients with quiescent Crohn's disease. Arena initiated the Phase IIb Captivate trial in late July 2019 in patients with irritable bowel syndrome related pain, in constipation and diarrhea predominant sub-types. The Phase IIb trial is expected to enroll 240 participants between the ages of 18 and 70.Three doses of 10 mg, 25 mg, and 50 mg are being tested against Placebo in a 3:4 prescription ratio with a Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor) masking layout.
Peripherally acting μ-opioid receptor antagonists (PAMORAs) are a class of chemical compounds that are used to reverse adverse effects caused by opioids interacting with receptors outside the central nervous system (CNS), mainly those located in the gastrointestinal tract. PAMORAs are designed to specifically inhibit certain opioid receptors in the gastrointestinal tract and with limited ability to cross the blood–brain barrier. Therefore, PAMORAs do not affect the analgesic effects of opioids within the central nervous system.
