Misoprostol diarrhea with

Diarrhea, with or without abdominal pain and cramps, occurs in up to 30% of patients who take misoprostol. Apparently dose-related, it typically begins within the first 2 weeks after therapy is initiated and often resolves spontaneously within a week more severe or protracted cases may necessitate drug discontinuation. Misoprostol can cause clinical exacerbations of inflammatory bowel disease (see Chapter 38) and should be avoided in patients with this disorder. Misoprostol is contraindicated during pregnancy because it can increase uterine contractility. 

Misoprostol is a synthetic prostaglandin E2 analog that exogenously replaces prostaglandin stores. The minimum effective dose shown to inhibit acid secretion and promote mucosal defense is 400 meg/day. Misoprostol use is limited by a high frequency of bothersome gastrointestinal effects such as abdominal pain, flatulence, and diarrhea. In placebo-controlled studies diarrhea occurred with twice the frequency in the... 

Misoprostol (B) is a semisynthetic prostaglandin derivative with greater stability than natural prostaglandin, permitting absorption after oral administration. like locally released prostaglandins, it promotes mucus production and inhibits acid secretion. Additional systemic effects (frequent diarrhea risk of precipitating contractions of the Liillmann, Color Atlas of Pharmacology (... 

Diarrhea Diarrhea (13% to 40%) is dose-related, usually develops early in the course of therapy (after 13 days), and usually is self-limiting (often resolving after 8 days), but requires discontinuation of misoprostol in some of patients. The incidence of diarrhea can be minimized by administering after meals and at bedtime and by avoiding coadministration of misoprostol with magnesium-containing antacids. 

Adverse reactions associated with misoprostol may include abdominal pain (7% to 20%), diarrhea (13% to 40%), and nausea (3%). 

Antiprogestins (eg, mifepristone) have been combined with an oral oxytocic synthetic analog of PGE1 (misoprostol) to produce early abortion. This regimen is available in the USA and Europe (see Chapter 39). The ease of use and the effectiveness of the combination have aroused considerable opposition in some quarters. The major toxicities are cramping pain and diarrhea. The oral and vaginal routes of administration are equally effective, but the vaginal route has been associated with an increased incidence of sepsis, so the oral route is now recommended. 

Gastrointestinal ulceration may occur less frequently than with some other NSAIDs. A preparation combining diclofenac and misoprostol decreases upper gastrointestinal ulceration but may result in diarrhea. Another combination of diclofenac and omeprazole was also effective with respect to the prevention of recurrent bleeding, but renal adverse effects were common in high-risk patients. Diclofenac, 150 mg/d, appears to impair renal blood flow and glomerular filtration rate. Elevation of serum aminotransferases occurs more commonly with this drug than with other NSAIDs. 

The most common adverse effect seen with the use of misoprostol is diarrhea, but abdominal pain has also been reported, limiting the use of this and other similar compounds in the management of gastroduodenal ulceration. Effects on uterine contraction have also been reported, suggesting that misoprostol should not be given to pregnant women (335). 

There is an increased risk of diarrhea in patients taking misoprostol with the m nesium-containing antacids. Sulfasalazine may increase the risk of toxicity of oral hypoglycemic dru, zidovudine, methotrexate, and phenytoin. There is an increased risk of crys-talluria when sulfasalazine is administered with medienamine. A decrease in the absorption of iron and folic acid may occur when these ents are administered with sulfasalazine. When bismuth subsalicylate is administered witli aspirin-containing dru, there is an increased risk of salicylate toxicity. There is an increased risk of toxicity of valproic acid and methotrexate and decreased effectiven s of the corticosteroids when these agents are administered with bismuth subsalicylate. 

Significant side effects are those associated with its abortifacient properties and other smooth muscle contraction effects, e.g., diarrhea and abdominal pain. Misoprostol also is an effective cervical ripening agent (by vaginal application) for the induction of labor. Other unlabeled uses include the treatment of postpartum hemorrhage and, with mifepristone, termination of pregnancy. 

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