Prescription medication · Antidiarrheal Combination

diphenoxylate/atropine

Also sold as Lomotil. Lomotil is used to treat diarrhea in people 13 years and older.

Data updated 2026-05-15

1
InteractionFew interactions
$2.89
Brand price (NADAC)

diphenoxylate/atropine (Lomotil) is a prescription Antidiarrheal Combination. Lomotil is used to treat diarrhea in people 13 years and older.

Lomotil is a drug that helps manage diarrhea. It contains two medicines, diphenoxylate and atropine, to slow down your bowels.

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Drug Pricing (NADAC)

Brand Price

$2.89/unit

Generic Available

No

PFIZER

Pricing data from NADAC (CMS), effective December 18, 2024. Compare all drug costs →

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What it does

Lomotil is used to treat diarrhea in people 13 years and older.

Common side effects

Numbness in your arms and legs, Feeling of well-being, Depression

Key warnings

Lomotil can cause serious side effects, including breathing problems and nervous system issues.

The sections below are summarized in plain English from diphenoxylate/atropine's FDA-approved prescribing information. They describe what the official label says, and are not personal medical advice.

How It Works

Lomotil works by slowing down the movement of your intestines. Diphenoxylate reduces bowel contractions. Atropine is added to discourage people from taking too much of this medicine.

Serious Warnings

Lomotil can cause serious side effects, including breathing problems and nervous system issues. Dehydration and electrolyte imbalance can also occur. If you have an infection causing your diarrhea, Lomotil can make it worse. Do not use if you are under 6 years old.

Known Drug Interactions

minor buspirone

Other Drugs that Cause CNS Depression The concurrent use of Lomotil with other drugs that cause CNS depression (e.g., barbiturates, benzodiazepines, opioids, buspirone, antihistamines, muscle relaxants), may potentiate the effects of Lomotil (see WARNINGS ).

Mechanism: Both of these medicines can slow down the central nervous system, and taking them together can make these drowsy effects much stronger.

This is a plain-language summary of FDA-label interaction records and does not provide individual medication-combination directions.

Common Questions

Who should not take Lomotil?
Children under 6 years old, people with certain types of diarrhea caused by infection, people with jaundice, and people allergic to diphenoxylate or atropine should not take Lomotil.
Can I drink alcohol while taking Lomotil?
No, avoid alcohol while taking Lomotil, as it can increase drowsiness.
What should I do if Lomotil doesn't improve my diarrhea?
If your diarrhea does not improve after 10 days of taking the maximum dose, stop taking Lomotil and talk to your doctor.
Can Lomotil cause constipation?
Yes, Lomotil can slow down your bowels too much and cause constipation.
Can I take Lomotil with other medications?
Lomotil can interact with other medicines that cause drowsiness, such as sleeping pills, antihistamines, and muscle relaxants. Tell your doctor about all the medicines you take.
What are the signs of an overdose?
Signs of overdose include slow breathing, confusion, rapid heartbeat, fever, and dry skin. Seek medical attention immediately if you suspect an overdose.
How quickly does Lomotil work?
You should see improvement in your diarrhea within 48 hours.
Can Lomotil cause allergic reactions?
Yes, allergic reactions such as rash, hives, and swelling can occur. Seek medical attention if you experience these symptoms.
Is Lomotil a cure for diarrhea?
No, Lomotil helps manage the symptoms of diarrhea. It is important to treat the underlying cause of your diarrhea.
What if I am taking an MAOI?
Avoid Lomotil if you take an MAOI or monitor for signs of high blood pressure.
What are the common side effects of diphenoxylate/atropine?
The registry lists Numbness in your arms and legs, Feeling of well-being, Depression, Feeling tired or weak, Confusion among the most-reported FAERS reaction terms for diphenoxylate/atropine. These counts are not an individual symptom assessment.
Does diphenoxylate/atropine interact with other medications?
The registry has 1 documented interaction rows for diphenoxylate/atropine. Notable source-record pairings include buspirone. These rows are not a complete medication review.
What drug class is diphenoxylate/atropine?
diphenoxylate/atropine belongs to the Antidiarrheal Combination drug class. It requires a prescription (Rx). Lomotil is used to treat diarrhea in people 13 years and older.
What pregnancy or breastfeeding source fields are listed for diphenoxylate/atropine?
The FDA label for diphenoxylate/atropine contains product-specific pregnancy or breastfeeding language. PlainMeds does not apply that source text to an individual.

Related Medications in Antidiarrheal Combination

Other drugs grouped near diphenoxylate/atropine - same-class peers and common alternatives.

alosetron

Lotronex

Alosetron (Lotronex) is a medicine for women with severe diarrhea-predominant irritable bowel syndrome (IBS).

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aprepitant

Emend

Aprepitant (Emend) is a medicine that helps prevent nausea and vomiting.

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bisacodyl

Dulcolax

Bisacodyl is a medicine that helps you have a bowel movement.

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bismuth subsalicylate

Pepto-Bismol

Bismuth subsalicylate (Pepto-Bismol) is a medicine that can treat diarrhea and upset stomach.

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cimetidine

Tagamet

Cimetidine (Tagamet) reduces stomach acid.

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Compare diphenoxylate/atropine vs alosetron side-by-side →

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What the FDA Data Shows for diphenoxylate/atropine

The FDA label for diphenoxylate/atropine (sold under brand names such as Lomotil) classifies it as a prescription-only medication in the Antidiarrheal Combination class. Lomotil is used to treat diarrhea in people 13 years and older. Official labeling lists 9 commonly reported side effects, including Numbness in your arms and legs, Feeling of well-being, Depression.

Post-market surveillance from the FDA Adverse Event Reporting System (FAERS) captures real-world experience. Voluntary reports accumulate over the lifetime of a drug and reflect wide-ranging clinical use. The database also lists 1 documented drug interaction derived from FDA labeling, with the top-flagged interaction rated minor severity. NADAC pricing from CMS.

Report counts do not establish causation, a FAERS entry documents a temporal association, not proof that the drug produced the outcome. Widely prescribed medications naturally accumulate more reports than niche therapies, so raw totals must be interpreted alongside total exposure. Shortage status, recall history, and patent information are separate source-record fields. This page is a public FDA/CMS registry and does not provide medical, treatment, substitution, or medication-change directions.

Data Sources

Drug labeling: FDA Drug Labels (SPL/DailyMed). Adverse events: FDA Adverse Event Reporting System (FAERS). Pricing: CMS National Average Drug Acquisition Cost (NADAC).

FAERS reports are voluntary and do not establish causation. Drug interactions are derived from FDA labeling and clinical references. This registry does not provide medication decisions.

Last updated: April 3, 2025

PlainMeds is rendered directly from FDA openFDA/FAERS extracts, DailyMed labels, and CMS drug-pricing files, no number is typed in by an editor. FAERS counts, recalls, shortages, and price figures on this page are queried live from those federal extracts. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2026-05-15. Primary sources: openFDA / FAERS, DailyMed and CMS Part B ASP.

Read our methodology - how this data is sourced, computed, and verified.

Data currency: FDA FAERS adverse-event reports through 2025, CMS NADAC acquisition-cost pricing effective December 2024, compiled from the source snapshot dated . See our methodology for per-source dates and refresh cadence. Spot a figure that looks wrong? Report a data issue.

All federal data sources used on this page