Loperamide / simethicone Side Effects
For the Consumer
Applies to loperamide / simethicone: tablets
No COMMON side effects have been reported with this product. Seek medical attention right away if any of these SEVERE side effects occur while taking loperamide / simethicone:
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); constipation; decreased urination; red, swollen, blistered, or peeling skin; stomach bloating, swelling, or pain.
For Healthcare Professionals
Applies to loperamide / simethicone: oral tablet, oral tablet chewable
Necrotizing enterocolitis with perforation was reported in two women following short courses (24 hours and 3 days) of loperamide for the treatment of acute diarrhea with fever. Resected bowel in both cases revealed extensive mucosal hemorrhage and necrosis.
Toxic megacolon has been reported in association with the use of loperamide to treat symptoms of ulcerative colitis and pseudomembranous colitis due to antibiotic therapy. In one patient treated for ulcerative colitis, abdominal symptoms seemed to improve in the days before requiring emergency laparotomy.
Loperamide has also been implicated in a case of appendicitis. A 35-year-old male self-treated travelers' diarrhea with loperamide at greater than recommended daily dose for seven days. Three days later, an appendolith was noted during an emergency appendectomy. The authors speculated that fecal stasis induced by loperamide increases the risk of fecalith and appendolith formation, the latter being associated with the pathogenesis of appendicitis.
Gastrointestinal side effects reported during loperamide therapy are often likely due to the underlying illness and include nausea, vomiting, dyspepsia, abdominal cramps and anorexia.
Cases of paralytic ileus associated with abdominal distention have been reported rarely with use of loperamide. Many of these reports had occurred in a setting with acute dysentery, overdose, and children less than 2 years old.[Ref]
Gastrointestinal side effects of loperamide have included nausea, vomiting, dyspepsia, abdominal cramps, anorexia, abdominal pain, abdominal distention, dry mouth, abdominal discomfort, and constipation. Gastrointestinal side effects have rarely included ileus, toxic megacolon, and necrotizing enterocolitis with or without perforation.[Ref]
Nervous system side effects of loperamide have rarely included drowsiness, tiredness, dizziness and severe central nervous system depression.[Ref]
Severe central nervous system depression may occur with overdose of loperamide.[Ref]
Other side effects of loperamide have rarely included physical dependence.[Ref]
While structurally related to meperidine and diphenoxylate, abuse potential is very low with loperamide. At therapeutic doses, it does not produce euphoria.
In opioid addicted monkeys, loperamide in high doses did prevent withdrawal symptoms.
A 26-year-old male with a history of opioid and alcohol abuse, began taking loperamide for the treatment of acute diarrhea. Despite denying euphoric effects from the drug, he gradually increased his intake to 320 mg per day. Attempts to stop the drug resulted in acute withdrawal (chest pain, shortness of breath, chills, diaphoresis, abdominal discomfort, nausea. and vomiting). Methadone relieved the symptoms. A slow methadone taper in an inpatient setting was successful in treating the physical dependence.[Ref]
Hypersensitivity side effects of loperamide have included skin rash. Anaphylactic shock and anaphylactoid reactions have been reported rarely.[Ref]
Dermatologic side effects have associated with loperamide therapy included rash, pruritus, urticaria, and angioedema. Bullous eruptions including erythema multiforme, Stevens-Johnson syndrome, and toxic epidermal necrolysis (TEN) have been reported rarely.[Ref]
Genitourinary side effects of loperamide have included urinary retention.[Ref]
Simethicone has no known side effects.[Ref]
1. Olm M, Gonzalez FJ, Garcia-Valdecasas JC, Fuster J, Bertran A, Milla J "Necrotising colitis with perforation in diarrhoic patients treated with loperamide." Eur J Clin Pharmacol 40 (1991): 415-6
2. Katz JP, Sturmann KM "Appendicitis associated with loperamide hydrochloride abuse." Ann Pharmacother 27 (1993): 369-70
3. Ericsson CD, Johnson PC "Safety and efficacy of loperamide." Am J Med 88 (1990): s10-4
4. Brown JW "Toxic megacolon associated with loperamide therapy." JAMA 241 (1979): 501-2
5. Walley T, Milson D "Loperamide related toxic megacolon in Clostridium difficile colitis." Postgrad Med J 66 (1990): 582
6. Forgue ST, Shyu WC, Gleason CR, et al "Pharmacokinetics of the novel cephalosporin cefepime (BMY-28142) in rats and monkeys." Antimicrob Agents Chemother 31 (1987): 799-804
7. Hill MA, Greason FC "Loperamide dependence." J Clin Psychiatry 53 (1992): 450
8. "Multum Information Services, Inc. Expert Review Panel"
Not all side effects for loperamide / simethicone may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.
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