From the Guidelines
Isotretinoin causes diarrhea and vomiting primarily through its irritant effect on the gastrointestinal mucosa and by altering intestinal motility, as supported by the most recent evidence 1. The exact mechanism by which isotretinoin causes gastrointestinal side effects such as diarrhea and vomiting is multifaceted.
- As a vitamin A derivative, isotretinoin can directly irritate the lining of the stomach and intestines, leading to inflammation that triggers nausea, vomiting, and diarrhea.
- Additionally, isotretinoin affects the secretion of mucus in the intestinal tract, potentially disrupting the protective barrier of the gut and increasing susceptibility to irritation.
- The medication may also influence gut motility by affecting smooth muscle function in the intestinal walls, leading to altered transit time of intestinal contents.
- Some patients experience these side effects due to isotretinoin's impact on bile acid metabolism, which can cause malabsorption of fats and subsequent diarrhea. These gastrointestinal side effects typically occur in about 10-20% of patients taking standard isotretinoin doses (0.5-1 mg/kg/day) and are usually dose-dependent, meaning higher doses tend to cause more pronounced symptoms, as noted in earlier studies 1. However, the most recent guidelines suggest that the risk of inflammatory bowel disease and other severe gastrointestinal side effects is not significantly increased with isotretinoin use 1. Patients can minimize these effects by taking isotretinoin with food and maintaining adequate hydration throughout treatment, as recommended in the guidelines 1. It is essential to monitor patients for these side effects and adjust treatment accordingly, while also considering the potential benefits of isotretinoin in the management of acne vulgaris, as outlined in the most recent guidelines 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Mechanism of Isotretinoin-Induced Diarrhea and Vomiting
- The mechanism by which isotretinoin causes diarrhea and vomiting is related to its effect on the intestinal mucosae, causing damage and leading to adverse effects such as bloody and mucousy diarrhea, colitis, and ileitis 2.
- Isotretinoin can affect all mucous membranes, causing multiple disorders of varying severity, including gastrointestinal tract disorders such as colitis 2.
- The exact mechanism of isotretinoin-induced diarrhea and vomiting is not fully understood, but it is thought to be related to the drug's ability to cause inflammation and damage to the intestinal lining 2.
- There is no direct evidence to suggest that isotretinoin causes diarrhea and vomiting through a specific mechanism, but rather it is a result of the drug's overall effect on the body's mucous membranes 2.
Management of Isotretinoin-Induced Diarrhea and Vomiting
- Loperamide, an antidiarrheal medication, may be effective in managing diarrhea caused by isotretinoin, but its effectiveness has not been specifically studied in this context 3, 4.
- Octreotide, a somatostatin analogue, has been shown to be effective in managing chemotherapy-induced diarrhea, but its use in isotretinoin-induced diarrhea has not been studied 5.
- Patients taking isotretinoin should be informed of the risk of mucosal damage and intestinal disorders, and should be monitored closely for signs of diarrhea and vomiting 2.