From the Guidelines
Loperamide is recommended as the first-line treatment for mild to moderate diarrhea in adults, with a starting dose of 4mg initially, followed by 2mg after each loose stool, not exceeding 16mg daily 1. The use of loperamide is supported by several studies, including a 2017 guideline for the prevention and treatment of travelers' diarrhea, which recommends loperamide as a non-antibiotic, anti-motility drug for the treatment of mild diarrhea 1. Some key points to consider when using loperamide include:
- It works by slowing down intestinal movement, allowing more water to be absorbed from stool
- It is effective for treating acute diarrhea and managing chronic diarrhea associated with inflammatory bowel disease or irritable bowel syndrome
- Side effects may include constipation, abdominal pain, nausea, and dizziness
- It should not be used in cases of bloody diarrhea, high fever, or diarrhea caused by certain bacterial infections like C. difficile
- Patients should seek medical attention if diarrhea persists beyond 2 days or is accompanied by severe symptoms Other studies, such as the 2018 ESMO clinical practice guidelines for the treatment of diarrhea in adult cancer patients, also recommend loperamide as a first-line treatment for diarrhea, with a starting dose of 4mg followed by 2mg every 2-4 hours or after every unformed stool 1. Additionally, the 2017 Infectious Diseases Society of America clinical practice guidelines for the diagnosis and management of infectious diarrhea recommend the use of loperamide in immunocompetent adults with acute watery diarrhea, but advise against its use in children under 18 years of age or in cases of suspected or proven toxic megacolon 1. Overall, the evidence supports the use of loperamide as a safe and effective treatment for mild to moderate diarrhea in adults, with a recommended starting dose of 4mg initially, followed by 2mg after each loose stool, not exceeding 16mg daily 1.
From the FDA Drug Label
INDICATIONS AND USAGE Loperamide hydrochloride capsules are indicated for the control and symptomatic relief of acute nonspecific diarrhea in patients 2 years of age and older and of chronic diarrhea in adults associated with inflammatory bowel disease. Loperamide hydrochloride capsules are also indicated for reducing the volume of discharge from ileostomies.
- Indications for Loperamide:
- Control and symptomatic relief of acute nonspecific diarrhea in patients 2 years of age and older
- Control and symptomatic relief of chronic diarrhea in adults associated with inflammatory bowel disease
- Reducing the volume of discharge from ileostomies 2
From the Research
Mechanism of Action
- Loperamide works by decreasing peristalsis and fluid secretion, resulting in longer gastrointestinal transit time and increased absorption of fluids and electrolytes from the gastrointestinal tract 3
- It is a phenylpiperidine derivative with a chemical structure similar to opiate receptor agonists such as diphenoxylate and haloperidol, but it has minimal central nervous system effects due to its low oral absorption and inability to cross the blood-brain barrier 3
Efficacy
- Loperamide is an effective treatment for patients with painless diarrhea and is considered to be free of abuse potential 3, 4
- It is more effective than diphenoxylate in providing symptomatic control of chronic diarrhoea 5
- Loperamide is also effective for the "gut-directed" symptom of diarrhea in patients with painless diarrhea or diarrhea-predominant irritable bowel syndrome 6
Safety and Side Effects
- Loperamide is a safe drug, with few adverse reactions reported worldwide 4
- Common adverse reactions to loperamide include cramps and nausea 3
- Loperamide is generally well tolerated at recommended nonprescription doses, with the most common side effects related to the impact on bowel motility (abdominal pain, distention, bloating, nausea, vomiting, and constipation) 6
Comparison to Other Treatments
- Loperamide provides more rapid control of symptoms than diphenoxylate when given in a flexible dosage according to unformed bowel movements 5
- Loperamide has a longer duration of action than diphenoxylate 5, 3
- Loperamide may prove to be the antidiarrheal agent of choice when compared with currently available nonprescription treatments for acute diarrhea 4