Over-the-counter medication · H2 Receptor Antagonist

famotidine

Also sold as Pepcid. This medicine treats active duodenal ulcers and active gastric ulcers.

Data updated 2026-05-15

110,018
FDA reportsOften reported
11
InteractionsSeveral interactions
2
Recall records

What the data shows

famotidine (Pepcid) is an over-the-counter H2 Receptor Antagonist, more reported than most tracked drugs (110,018 FDA reports), with 11 documented drug interactions.

Reporting volume reflects how widely a drug is used and studied, not how dangerous it is, a FAERS report documents a temporal association, never proof of cause.

famotidine (Pepcid) is an over-the-counter H2 Receptor Antagonist. This medicine treats active duodenal ulcers and active gastric ulcers.

Famotidine (Pepcid) reduces stomach acid. It is used to treat ulcers, heartburn, and acid reflux.

Verify with FDA → · CMS NADAC pricing →

Drug Pricing (NADAC)

Generic Price

$0.10/unit

Generic Available

Yes (48 manufacturers)

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

View Alternatives → Compare with Another Drug → Full Side Effects Report →

What it does

This medicine treats active duodenal ulcers and active gastric ulcers.

Common side effects

Headache, Dizziness, Constipation

Key warnings

In elderly patients and those with kidney problems, famotidine can cause confusion, delirium, or hallucinations.

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

How It Works

Famotidine is an H2 receptor antagonist. This means it blocks histamine, a substance that tells your stomach to make acid. By blocking histamine, famotidine reduces the amount of acid your stomach produces.

Side Effects (from patient reports)

Based on 110,018 FDA adverse event reports.

Most-reported reactions

Adverse reactions in FAERS for famotidine, by number of reports

reports

What this shows Bars show how often each reaction was reported, not how likely it is to happen, a report records a temporal association, never proof that the drug caused it.

Source FDA Adverse Event Reporting System (FAERS) As of 2025

Reports over time

Adverse-event reports filed for famotidine each year to the FDA Adverse Event Reporting System (FAERS).

05,00010,00015,000 19952003200720112015201920232025 11,202

Year-to-year volume tracks usage, prescribing, and scrutiny, not a change in per-patient risk. Source: FDA FAERS.

Where famotidine sits

famotidine has more FDA adverse-event reports than 87% of the drugs FAERS tracks. A high position reflects how widely a drug is used and watched, not how dangerous it is.

fewest reports most reports

Percentile across all drugs PlainMeds tracks by FAERS report volume. The dot is famotidine; the line is the median (50th percentile).

FDA Adverse Event Report Analysis

Detailed analysis of 110,018 reports from the FDA Adverse Event Reporting System (FAERS). Reports span 1995–2025.

Total Reports

110,018

Reports Mentioning Death

10,287

9.4% of reports — not proof of cause

Hospitalization Reports

35,591

Top Indication

Product Used For Unknown Indication

Gender Distribution

Female 61,566 (62%)
Male 37,547 (38%)

Age Distribution

0–17 4,064
18–44 10,919
45–64 23,580
65–74 16,749
75+ 13,846

Most Reported Adverse Reactions (FAERS)

# Reaction Reports
1 NAUSEA 7,258
2 FATIGUE 6,866
3 CHRONIC KIDNEY DISEASE 6,644
4 DIARRHOEA 6,452
7 DYSPNOEA 5,202
8 HEADACHE 4,907
9 ACUTE KIDNEY INJURY 4,660
10 PAIN 4,619
11 VOMITING 4,464
12 DIZZINESS 4,226
13 RENAL FAILURE 4,104
14 DEATH 3,690
15 PNEUMONIA 3,504
16 ASTHENIA 3,363
17 PYREXIA 3,343

Reactions in Death Reports

DEATH 3,672
PNEUMONIA 726
RENAL FAILURE 724
CHRONIC KIDNEY DISEASE 715
ACUTE KIDNEY INJURY 712
SEPSIS 585
RESPIRATORY FAILURE 535
DYSPNOEA 486
NAUSEA 464
END STAGE RENAL DISEASE 462

Reactions in Hospitalization Reports

PNEUMONIA 2,739
NAUSEA 2,675
DIARRHOEA 2,463
DYSPNOEA 2,438
VOMITING 2,230
PYREXIA 2,147
FATIGUE 2,073
PAIN 1,720
FALL 1,713
ACUTE KIDNEY INJURY 1,690

Source: FDA FAERS (Adverse Event Reporting System) Reports are voluntary and do not establish causation

Serious Warnings

In elderly patients and those with kidney problems, famotidine can cause confusion, delirium, or hallucinations. If you are elderly or have kidney problems, your doctor may prescribe a lower dose. Famotidine can hide the symptoms of stomach cancer. If your symptoms don't improve, tell your doctor.

Known Drug Interactions

major theophylline

albuterol, systemic and inhaled mebendazole amoxicillin medroxyprogesterone ampicillin, with or without sulbactam methylprednisolone atenolol metronidazole azithromycin metoprolol caffeine, dietary ingestion nadolol cefaclor nifedipine co-trimoxazole (trimethoprim and sulfamethoxazole) nizatidine diltiazem norfloxacin dirithromycin ofloxacin enflurane omeprazole famotidine prednisone, prednisolone felodipine ranitidine finasteride rifabutin hydrocortisone roxithromycin isoflurane Sorbitol (purgative doses do not inhibit theophylline absorption) isoniazid sucralfate isradipine terbutaline,...

Mechanism: Famotidine does not affect the amount of theophylline that stays in your blood.

moderate tizanidine

( 7.1 ) • Tizanidine (CYP1A2) Substrate: Potential for substantial increases in blood concentrations of tizanidine resulting in hypotension, bradycardia or excessive drowsiness; avoid concomitant use, if possible. 7.2 Tizanidine (CYP1A2 Substrate) Although not studied clinically, famotidine is considered a weak CYP1A2 inhibitor and may lead to substantial increases in blood concentrations of tizanidine, a CYP1A2 substrate. Refer to the full prescribing information for tizanidine.

Mechanism: Famotidine can slow down the body's ability to clear tizanidine, which may lead to dangerously high levels of the drug in your blood.

minor ketoconazole

See the prescribing information for other drugs dependent on gastric pH for absorption for administration instructions, including atazanavir, erlotinib, ketoconazole, itraconazole, ledipasvir/sofosbuvir, nilotinib, and rilpivirine.

Mechanism: Famotidine reduces stomach acid, which can prevent ketoconazole from being absorbed into your system.

minor ledipasvir/sofosbuvir

See the prescribing information for other drugs dependent on gastric pH for absorption for administration instructions, including atazanavir, erlotinib, ketoconazole, itraconazole, ledipasvir/sofosbuvir, nilotinib, and rilpivirine.

Mechanism: Famotidine lowers stomach acid, which can make it harder for the body to absorb ledipasvir/sofosbuvir.

minor itraconazole

See the prescribing information for other drugs dependent on gastric pH for absorption for administration instructions, including atazanavir, erlotinib, ketoconazole, itraconazole, ledipasvir/sofosbuvir, nilotinib, and rilpivirine.

Mechanism: Famotidine reduces stomach acid, which is needed for the body to properly absorb itraconazole.

Check all your medications →

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

Common Questions

Can I take famotidine with other medications?
Famotidine can affect how other drugs are absorbed. Talk to your doctor about all the medicines you take.
How long does it take for famotidine to work?
Famotidine usually starts to work within an hour.
Can I drink alcohol while taking famotidine?
Talk to your doctor about drinking alcohol while taking famotidine.
What should I do if I experience side effects?
Tell your doctor if you experience any side effects that bother you or do not go away.
Can I take famotidine long-term?
Talk to your doctor about how long you should take famotidine.
Is there a weight limit for children taking this medication?
Famotidine tablets are not recommended for children weighing less than 40 kg.
What should I do if my heartburn comes back after stopping famotidine?
Talk to your doctor if your heartburn comes back after you stop taking famotidine.
Can famotidine cause any serious side effects?
In rare cases, famotidine can cause serious side effects. Seek medical attention right away if you experience any signs of a serious allergic reaction.
Does famotidine interact with any specific foods?
Famotidine can be taken with or without food.
Can I crush or chew the tablet?
Swallow the tablet whole. Do not crush or chew it.
What are the common side effects of famotidine?
The registry lists Headache, Dizziness, Constipation, Diarrhea among the most-reported FAERS reaction terms for famotidine. The compiled record contains 110,018 FDA adverse-event reports. These counts are not an individual symptom assessment.
Does famotidine interact with other medications?
The registry has 11 documented interaction rows for famotidine. Notable source-record pairings include theophylline, tizanidine, ketoconazole. These rows are not a complete medication review.
What drug class is famotidine?
famotidine belongs to the H2 Receptor Antagonist drug class. It is available over the counter (OTC). This medicine treats active duodenal ulcers and active gastric ulcers.
What pregnancy or breastfeeding source fields are listed for famotidine?
The FDA label for famotidine contains product-specific pregnancy or breastfeeding language. PlainMeds does not apply that source text to an individual.
Has famotidine been recalled?
There are 2 recalls associated with famotidine products. Microbial Contamination of Sterile Products; out of limit results obtained for endotoxin testing. Check the recalls section below for full details and affected products.

Active Recalls

Class I November 6, 2025

Microbial Contamination of Sterile Products; out of limit results obtained for endotoxin testing.

Fresenius Kabi USA, LLC

Class II June 23, 2022

CGMP Deviations: product held outside appropriate storage temperature conditions.

Family Dollar Stores, Llc.

Related Medications in H2 Receptor Antagonist

Other drugs grouped near famotidine - same-class peers and common alternatives.

alosetron

Lotronex

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

Compare with famotidine →

aprepitant

Emend

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

Compare with famotidine →

bisacodyl

Dulcolax

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

Compare with famotidine →

bismuth subsalicylate

Pepto-Bismol

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

Compare with famotidine →

cimetidine

Tagamet

Cimetidine (Tagamet) reduces stomach acid.

Compare with famotidine →

Compare famotidine vs alosetron side-by-side →

Compare beyond drug class

Nationwide peers by FAERS volume & death-report share

Two PlainMeds-derived comparison paths for famotidine: nearest FDA FAERS report volume and nearest death-report share among drugs with at least 1,000 logged reports, excluding same-class neighbors listed above. Counts reflect reporting volume, not proven individual harm.

Similar FAERS report volume

Nearest drugs by total FAERS reports. This record: 110,018.

4 peers

Similar death-report share

Nearest drugs by FAERS death-report share. This record: 9.35%.

4 peers

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What the FDA Data Shows for famotidine

The FDA label for famotidine (sold under brand names such as Pepcid) classifies it as an over-the-counter product in the H2 Receptor Antagonist class. This medicine treats active duodenal ulcers and active gastric ulcers. Official labeling lists 4 commonly reported side effects, including Headache, Dizziness, Constipation.

Post-market surveillance from the FDA Adverse Event Reporting System (FAERS) captures real-world experience. For this drug, FAERS contains 110,018 voluntary reports. The database also lists 11 documented drug interactions derived from FDA labeling, with the top-flagged interaction rated major severity. NADAC pricing from CMS shows a generic unit cost of $0.10.

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 (currently 2 recall records on file), 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: October 22, 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