• See Also
  1. Acute Diarrhea
  • Indications
  1. Acute Diarrhea
  • Contraindications
  1. Clostridioides difficile
  2. Dysentery (toxigenic Diarrhea)
  3. Child under age 6 years
    1. Risk of respiratory depression (anoxic brain injury and death has occurred)
  4. Down Syndrome (risk of Atropine toxicity, even at low dose)
  5. Elderly (relative contraindication, risk of Atropine toxicity)
  • Mechanism
  1. Diphenoxylate is typically combined with Atropine (Lomotil) for use as an antidiarrheal
  2. Diphenoxylate is a peripherally acting Opioid acting at gastrointestinal Opioid receptors
    1. Piperidine derivative similar in structure to Meperidine
    2. No significant central activity or Analgesic effect (retained in Gastrointestinal Tract due to insolubility)
  • Preparations
  1. Diphenoxylate/Atropine Tablets (2.5 mg/0.025 mg tablet)
  2. Diphenoxylate/Atropine Solution (2.5 mg/0.025 mg per 5 ml)
  1. Adult
    1. Take 2 tabs (or 10 ml) orally up to 4 times daily as needed
  2. Child
    1. Give 0.3 to 0.4 mg Diphenoxylate per kg per day in 4 divided doses
      1. Age 9 to 12 years (weight 23 to 55 kg): 3.5 to 5 ml orally 4 times daily
      2. Age 6 to 8 years (weight 17 to 32 kg): 2.5 to 5 ml orally 4 times daily
    2. Maximum 20 mg Diphenoxylate per day
  • Safety
  1. Pregnancy Category C
  2. Safe in Lactation
  • Drug Interactions
  1. CNS Depressants
    1. Diphenoxylate with Atropine may potentiate CNS Depressant effect
  2. MAO Inhibitors
    1. Hypertension risk
  3. Anticholinergic Medications
    1. Increased ileus risk
  • Resources
  1. Diphenoxylate and Atropine, Lomotil (DailyMed)
    1. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=6f76c6d2-7a30-43cd-8c2b-d6a12f8fc867
  • References
  1. Hamilton (2020) Tarascon Pocket Pharmacopoeia
  2. Olson (2020) Clinical Pharmacology, Medmaster Miami, p. 96