Loperamide
IMODIUM
What it isPeripherally restricted mu agonist slowing gut transit; diarrhea.
Why this oneP-glycoprotein keeps it out of the CNS, so it controls diarrhea without euphoria or dependence at normal doses.
What limits itAt the supratherapeutic doses used for abuse it saturates P-gp and causes torsades and death. Avoid in inflammatory or invasive colitis.
FDA-approved for
- diarrhea (1976)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Diarrhea (OTC) | Adults & children ≥12 yr | 2 caplets after first loose stool, then 1 after each subsequent loose stool | 4 caplets/24 hr | |
| Diarrhea (OTC) | Children 9–11 yr (60–95 lb) | 1 caplet after first loose stool, then ½ after each subsequent | 3 caplets/24 hr | |
| Diarrhea (OTC) | Children 6–8 yr (48–59 lb) | 1 caplet after first loose stool, then ½ after each subsequent | 2 caplets/24 hr |
Renal Undefined
Hepatic Undefined
Instructions
- Drink plenty of clear fluids to prevent dehydration
- Children 2–5 yr (34–47 lb): ask a doctor; children under 2 yr: do not use
Pregnancy Undefined
Lactation Undefined
NO BOXED WARNINGS
Principal riskTorsades at the supratherapeutic doses used for abuse
Cost, est. cash$5–$150/month
Generic entry1991
Classes and tags
Clinical profile
Legacy pregnancy categoryC
Defining liabilityTherapeutic CNS effects are minimal, but high-dose misuse can cause fatal sodium/potassium-channel cardiotoxicity.
Mechanism of action: Loperamide ballicule
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