Diphenoxylate and Atropine

Diagram of the molecular structure of Diphenoxylate and Atropine
Brand name: Lomotil®
Brand name: Lonox®
IUPAC: diphenoxylate: ethyl 1-[3-cyano-3,3-di(phenyl)propyl]-4-phenylpiperidine-4-carboxylate, atropine: (8-methyl-8-azabicyclo[3.2.1]oct-3-yl) 3-hydroxy-2-phenylpropanoate
FDA approval: Yes

Diphenoxylate and atropine is a combination drug that is most commonly known as Lomotil® or Lonox®. This drug works to treat diarrhea by slowing the passage of waste through the bowel to allow for more complete absorption of water and nutrients. This drug is given as an oral tablet or liquid.


Diphenoxylate is an antidiarrheal agent, which works by decreasing activity of the bowel by stimulating receptors in the gastrointestinal tract.1

  • 1. Dipenoxylate. MedlinePlus. https://medlineplus.gov/druginfo/meds/a601045.html
Side effects:

Common side effects include: dizziness, drowsiness, headache, blurred vision, dry mouth, constipation, difficult urination, and rash or itchy skin. This medicine should be used in conjunction with fluids to prevent dehydration. Dosage recommendations should be strictly adhered to, especially in children, as overdosage can cause respiratory depression and/or coma. This drug may also be habit-forming if taken incorrectly. Alcohol and other drugs can intensify some of these side effects. Patients should consult with a healthcare professional before taking other drugs.1

  • 1. Dipenoxylate. MedlinePlus. https://medlineplus.gov/druginfo/meds/a601045.html