Chemical: Drug

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2D structure from PubChem
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Generic Names
  • Dea No. 9170
  • Difenossilato [Dcit]
  • Difenoxilato [INN-Spanish]
  • Diphenoxalate
  • Diphenoxylate Hydrochloride
  • Diphenoxylatum [INN-Latin]
Trade Names
  • Lomotil
Brand Mixture Names
  • Lomotil (Atropine Sulfate + Diphenoxylate Hcl)

PharmGKB Accession Id





A meperidine congener used as an antidiarrheal, usually in combination with atropine. At high doses, it acts like morphine. Its unesterified metabolite difenoxin has similar properties and is used similarly. It has little or no analgesic activity. This medication is classified as a Schedule V under the Controlled Substances Act by the Food and Drug Administration (FDA) and the DEA in the United States when used in preparations. When diphenoxylate is used alone, it is classified as a Schedule II.

Source: Drug Bank


For as adjunctive therapy in the management of diarrhea

Source: Drug Bank

Other Vocabularies

Information pulled from DrugBank has not been reviewed by PharmGKB.

Pharmacology, Interactions, and Contraindications

Mechanism of Action

Diphenoxylate is an opiate receptor agonists that stimulate mu receptors in GI to decrease the peristalsis and constrict the sphincters. Diphenoxylate has a direct effect on circular smooth muscle of the bowel, that conceivably results in segmentation and prolongation of gastrointestinal transit time. The clinical antidiarrheal action of diphenoxylate may thus be a consequence of enhanced segmentation that allows increased contact of the intraluminal contents with the intestinal mucosa.

Source: Drug Bank


Diphenoxylate, an antidiarrheal, is effective as adjunctive therapy in the management of diarrhea. Diphenoxylate is rapidly and extensively metabolized in man by ester hydrolysis to diphenoxylic acid (difenoxine), which is biologically active and the major metabolite in the blood.

Source: Drug Bank

Food Interaction

Avoid alcohol.|Take with food.

Source: Drug Bank

Absorption, Distribution, Metabolism, Elimination & Toxicity



Source: Drug Bank

Protein Binding


Source: Drug Bank



Source: Drug Bank


12-14 hours

Source: Drug Bank


Coma, dry skin and mucous membranes, enlarged pupils of the eyes, extremely high body temperature, flushing, involuntary eyeball movement, lower than normal muscle tone, pinpoint pupils, rapid heartbeat, restlessness, sluggishness, suppressed breathing

Source: Drug Bank

Chemical Properties

Chemical Formula


Source: Drug Bank

Isomeric SMILES


Source: OpenEye

Canonical SMILES


Source: Drug Bank

Average Molecular Weight


Source: Drug Bank

Monoisotopic Molecular Weight


Source: Drug Bank

Genes that are associated with this drug in PharmGKB's database based on (1) variant annotations, (2) literature review, (3) pathways or (4) information automatically retrieved from DrugBank, depending on the "evidence" and "source" listed below.

Drug Targets

Gene Description
OPRD1 (source: Drug Bank)
OPRM1 (source: Drug Bank)

Drug Interactions

Drug Description
diphenoxylate Possible antagonism of action (source: Drug Bank)
diphenoxylate Possible antagonism of action (source: Drug Bank)

Relationships from National Drug File - Reference Terminology (NDF-RT)

May Treat
Contraindicated With

Publications related to diphenoxylate: 1

No Dosing Guideline available No Drug Label available No Clinical Annotation available No Variant Annotation available No VIP available No VIP available
Uniform assessment and ranking of opioid μ receptor binding constants for selected opioid drugs. Regulatory toxicology and pharmacology : RTP. 2011. Volpe Donna A, et al. PubMed


Web Resource:
National Drug Code Directory:
KEGG Drug:
PubChem Compound:
PubChem Substance:
Therapeutic Targets Database:
FDA Drug Label at DailyMed:

Clinical Trials

These are trials that mention diphenoxylate and are related to either pharmacogenetics or pharmacogenomics.

No trials found.

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Sources for PharmGKB drug information: DrugBank, Open Eye Scientific Software.