PlainMeds provides educational information only. This is not medical advice. Always consult your doctor or pharmacist.

nizatidine

Verify with FDA → · CMS NADAC pricing →

Brand names: Axid

H2 Receptor Antagonist OTC

Nizatidine helps reduce stomach acid. It can treat ulcers and heartburn.

Drug Pricing (NADAC)

Generic Price

$0.90/unit

Generic Available

Yes (4 manufacturers)

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

What it does

Nizatidine can treat active duodenal ulcers for up to 8 weeks.

Common side effects

Headache, Abdominal pain, Diarrhea

Key warnings

If you have kidney problems, your doctor may need to lower your dose.

How It Works

Nizatidine is an H2 receptor antagonist. This means it blocks histamine from attaching to cells in your stomach. By blocking histamine, the drug reduces the amount of acid your stomach makes.

How to Take It

For an active duodenal ulcer, take 300 mg once a day at bedtime, or 150 mg twice a day. To prevent ulcers, take 150 mg once a day at bedtime. For GERD, take 150 mg twice a day. For an active benign gastric ulcer, take 150 mg twice a day or 300 mg once a day at bedtime.

Pregnancy & Breastfeeding

Tell your doctor if you are pregnant or plan to become pregnant. It is not known if nizatidine will harm your unborn baby. Talk to your doctor if you are breastfeeding.

Missed Dose

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule.

Storage

Store at room temperature, between 68° to 77°F, in a tightly closed container away from light.

Side Effects (from patient reports)

Based on 981 FDA adverse event reports.

Long-term kidney disease
264
Sudden kidney damage
161
Kidney failure
135
Final stage of kidney disease
72
Feeling sick to your stomach
67
Throwing up
66
Kidney damage
59
GERD, acid reflux
56
Shortness of breath
53
Loose stools
48

FDA Adverse Event Report Analysis

Detailed analysis of 1,480 reports from the FDA Adverse Event Reporting System (FAERS). Reports span 1999–2025.

Total Reports

1,480

Death-Related Reports

157

Hospitalization Reports

566

Top Indication

Product Used For Unknown Indication

Gender Distribution

Female 803 (60%)
Male 529 (40%)

Age Distribution

0–17 19
18–44 135
45–64 344
65–74 257
75+ 243

Most Reported Adverse Reactions (FAERS)

# Reaction Reports
1 CHRONIC KIDNEY DISEASE 264
2 ACUTE KIDNEY INJURY 161
3 RENAL FAILURE 135
4 END STAGE RENAL DISEASE 72
5 NAUSEA 69
6 VOMITING 66
7 RENAL INJURY 59
8 GASTROOESOPHAGEAL REFLUX DISEASE 56
9 DYSPNOEA 53
10 DIARRHOEA 48
11 PYREXIA 48
12 DRUG INEFFECTIVE 47
13 DIZZINESS 45
14 MALAISE 45
15 ANAEMIA 44

Reactions in Death Reports

DEATH 27
CHRONIC KIDNEY DISEASE 23
ACUTE KIDNEY INJURY 18
PNEUMONIA 16
RENAL FAILURE 16
END STAGE RENAL DISEASE 13
MALIGNANT NEOPLASM PROGRESSION 13
PLATELET COUNT DECREASED 11
SEPSIS 11
PYREXIA 10

Reactions in Hospitalization Reports

PYREXIA 41
ACUTE KIDNEY INJURY 38
CHRONIC KIDNEY DISEASE 36
RENAL FAILURE 35
NAUSEA 31
ANAEMIA 30
DYSPNOEA 28
PNEUMONIA 28
MALAISE 26
VOMITING 24

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

Serious Warnings

If you have kidney problems, your doctor may need to lower your dose. Before taking this medicine for a stomach ulcer, make sure it is not cancerous.

Known Drug Interactions

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, s...

Mechanism: Nizatidine may interfere with the way your body breaks down theophylline, potentially increasing the risk of side effects.

What to do: Watch for signs of too much medicine, such as nausea or a racing heart, and report them to your healthcare provider.

Nizatidine) — An increase in gastric pH resulting from administration of nizatidine had no significant effect on pharmacokinetics.

Mechanism: Nizatidine changes the acid levels in the stomach, but this does not change how the body absorbs or uses tadalafil.

What to do: No special changes are needed when taking these two medicines together.

Common Questions

Can I take nizatidine with food?
The drug label does not specify whether to take it with food. Follow your doctor's instructions.
How long does it take for nizatidine to heal an ulcer?
Most patients' ulcers will heal within 4 weeks.
Can I take nizatidine long-term?
Yes, nizatidine can be used long-term at a reduced dose to prevent ulcers from returning, but the effects of using it for more than a year are unknown.
What should I do if I experience side effects?
Tell your doctor about any side effects you experience.
Can nizatidine be used for children?
The drug label does not include information about use in children. Talk to your doctor.
Does nizatidine interact with other medications?
The drug label does not include information about drug interactions. Talk to your doctor.
Can I drink alcohol while taking nizatidine?
The drug label does not include information about alcohol use. Talk to your doctor.
Is nizatidine available over the counter?
The drug label does not specify if it is available over the counter. Talk to your doctor.
What do the numbers on the capsules mean?
The numbers "3137" and "3138" are codes that identify the specific capsule.
What if my heartburn doesn't get better?
Talk to your doctor if your heartburn does not improve after taking nizatidine.
What are the common side effects of nizatidine?
The most commonly reported side effects of nizatidine include Headache, Abdominal pain, Diarrhea, Nausea, Dizziness. Based on 981 FDA adverse event reports. Always consult your healthcare provider about potential side effects.
Does nizatidine interact with other medications?
Yes, nizatidine has 2 known drug interactions. Notable interactions include theophylline, tadalafil. Always inform your doctor about all medications you are taking.
What drug class is nizatidine?
nizatidine belongs to the H2 Receptor Antagonist drug class. It is available over the counter (OTC). Nizatidine can treat active duodenal ulcers for up to 8 weeks.
Is nizatidine safe during pregnancy?
Tell your doctor if you are pregnant or plan to become pregnant. It is not known if nizatidine will harm your unborn baby. Always consult your healthcare provider before using any medication during pregnancy or breastfeeding.

Related Medications in H2 Receptor Antagonist

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

Compare nizatidine vs alosetron side-by-side →

Medication Guides

Related Health & Safety Data

What the FDA Data Shows for nizatidine

The FDA label for nizatidine (sold under brand names such as Axid) classifies it as an over-the-counter product in the H2 Receptor Antagonist class. Nizatidine can treat active duodenal ulcers for up to 8 weeks. Official labeling lists 6 commonly reported side effects, including Headache, Abdominal pain, Diarrhea.

Post-market surveillance from the FDA Adverse Event Reporting System (FAERS) captures real-world experience. For this drug, FAERS contains 981 voluntary reports. The database also lists 2 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 $0.90.

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 further shape supply and switching decisions. This page summarizes public FDA data for educational purposes only and is not a substitute for professional medical advice — always consult a licensed healthcare provider before starting, stopping, or changing any medication.

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. Always consult a healthcare professional before making medication decisions.

Last updated: June 30, 2022

All federal data sources used on this page