"Efficacy or Illusion?" Interpreting Null Results in the Rifaximin Trial

The placebo effect occurs when people's expectations or beliefs influence or determine their experience in a given situation. In other words, simply expecting something to happen can actually make it happen.

Serotonin, a crucial neurotransmitter synthesized by enterochromaffin cells, plays a cardinal role in regulating gastrointestinal (GI) motility. With over 90% of the body's total serotonin in the GI tract, its influence on digestive processes is profound. Serotonin is swiftly released upon various stimuli, such as food boluses or certain drugs, triggering intrinsic sensory neurons in the myenteric plexus and extrinsic vagal and spinal sensory neurons. This leads to the activation of the...

Diarrhea-predominant irritable bowel syndrome (IBS-D) is a subtype of IBS characterized primarily by frequent, loose, or watery stools, abdominal pain, and abdominal discomfort. Therapeutic approaches to managing IBS-D include dietary changes, stress management techniques, and pharmaceutical interventions.
Two specific drugs used in the treatment are alosetron (Lotronex) and eluxadoline (Viberzi). Alosetron, a 5-HT3 antagonist, works by slowing the movement of stools in the gut, reducing bowel...

Pharmacological therapies for IBS-C are designed to alleviate abdominal discomfort and enhance bowel function. In patients with IBS-C, fiber supplements may help soften stools and decrease straining, but may also lead to increased gas production and bloating. Osmotic laxatives like milk of magnesia are frequently used to soften stools and increase stool frequency in IBS-C patients. In addition, two drugs approved for use in severe IBS-C adult cases are linaclotide (Linzess) and lubiprostone...

Generic intravenous (IV) drugs are considered bioequivalent to their branded counterparts due to their 100% bioavailability upon administration. However, variations in stability among different drug products can significantly influence their therapeutic performance, even if they are pharmaceutically equivalent.Cefuroxime, a prophylactic antimicrobial, is often used as a single-dose IV injection for patients undergoing coronary artery bypass grafting surgery. A 3 g dose typically provides...

The concept of therapeutic equivalence (TE) in drugs with multiple indications is complex. A generic drug may be therapeutically equivalent to a brand-name product for one specific indication, but this doesn't necessarily mean it's equivalent for all other indications. Evidence of TE in one patient group and bioequivalence shown in healthy volunteers can support—but not confirm—TE for other indications. However, definitive proof requires individual clinical studies for each...