Omeprazole for Dogs and Cats
Medically reviewed by Dr. Pippa Elliott, BVMS MRCVS · Last reviewed

Drug facts
Omeprazole
Omeprazole is a proton pump inhibitor that blocks stomach acid secretion. In dogs and cats it is the most commonly recommended gastroprotectant, used for ulcers, esophagitis, erosions, and severe upper GI irritation.
Treats
What Is Omeprazole for Dogs and Cats
Overview
Omeprazole is a medication that blocks acid secretion in the stomach. It was the first PPI developed, and it is now widely used in both humans and animals. In veterinary care, omeprazole is the most frequently recommended gastroprotectant, especially for dogs with upper gastrointestinal (GI) diseases.
It works by targeting the H+/K+ ATPase proton pump in stomach parietal cells, resulting in strong and long-lasting acid suppression. This reduction in stomach acidity allows the GI tract to heal from ulcers, erosions, and severe irritation.
Explore more digestive and GI medications in our Digestive section.
What Is Omeprazole for Dogs and Cats Used For
Omeprazole blocks the gastric proton pump, preventing the release of stomach acid. This raises the stomach’s pH, reduces irritation, and creates an ideal environment for ulcer healing and inflammation reduction. Its acid-blocking effect lasts 24 hours, especially when given before meals.
| Condition | Notes |
|---|---|
| Gastroduodenal ulcers/erosions (GUE) | Helps heal ulcers caused by disease or secondary conditions. |
| Esophagitis / Acid reflux | Reduces acid exposure to the esophagus. |
| Exercise-induced gastritis (working dogs) | Prevents stomach irritation in high-performance dogs. |
| Post-anesthesia reflux reduction | Decreases low pH reflux events during anesthesia. |
| Pancreatitis-related GI irritation | Supports healing of inflamed upper GI tissues.prescribed for oral bacterial infections. |
| Portal hypertension / liver disease | Helps prevent ulceration linked to systemic disease. |
Important: Overprescribing omeprazole is common. The ACVIM consensus warns against using it for nonspecific vomiting, mild diarrhea, or as routine NSAID prophylaxis without evidence of ulcers.
Drug Facts
Omeprazole is a proton pump inhibitor that significantly reduces acid secretion. It is available as a human and veterinary medication and comes in oral and injectable forms. In veterinary practice, it is often used for dogs with ulcers, esophagitis, or severe stomach irritation.
Common Brands
Prilosec, GastroGard, UlcerGard
Drug Class
Proton pump inhibitor (PPI)
Substance Classification
Not a controlled substance
Generic Status
Generic widely available
Availability
Prescription
Available forms
Omeprazole for Dogs and Cats Dosage Forms
Omeprazole is available in oral capsules, tablets, paste formulations (equine), and injectable forms used mainly in hospital settings. For dogs and cats, oral capsules/tablets are the most common. Daily or twice-daily dosing varies by condition severity.
Studies show that twice-daily (q12h) dosing provides stronger acid control than once-daily dosing. IV administration is often used in hospitalized dogs.
Tablets (30 pcs)
| Qty/Size | Price as low as | Price per unit |
|---|---|---|
| 10 mg | $8.00 | $0.27 |
| 20 mg | $10.00 | $0.33 |
| 40 mg | $15.00 | $0.50 |
Oral Suspension (Compounded)
| Qty/Size | Price as low as | Price per unit |
|---|---|---|
| 15 mL | $25.00 | $1.66 |
| 30 mL | $40.00 | $1.33 |
Injectable Omeprazole (Hospital Use)
| Qty/Size | Price as low as | Price per unit |
|---|---|---|
| IV formulation (per dose) | $18.00 | N/A |
Typical Dosing for Omeprazole for Dogs and Cats
Omeprazole is typically given before meals and often twice daily for best acid control. Long-term use may require tapering to prevent rebound acid production.
Oral Dosing
| Group | Typical Dose | Notes |
|---|---|---|
| Dogs | 0.7–1.1 mg/kg every 12 hours | Optimal acid suppression at twice-daily dosing. |
| Cats | 0.5–1 mg/kg every 12–24 hours | Often used for reflux and esophagitis. |
| Hospitalized dogs (severe cases) | 2 mg/kg/day IV | Used in intensive care settings. |
Long-Term Therapy
| Group | Typical Dose | Notes |
|---|---|---|
| Dogs and Cats | Gradual dose tapering | Prevents rebound hyperacidity. |
Reported side effects
Risks and Warnings for Omeprazole for Dogs and Cats
While omeprazole is considered safe, it can cause microbiome changes, nutritional effects, and interactions with other drugs.
GI Microbiome Changes
Omeprazole significantly alters gut bacteria in dogs:
- Decreases Helicobacter spp.
- Increases Lactobacillus, Streptococcus, and Enterococcus
- May decrease Faecalibacterium, a beneficial anti-inflammatory species
Potential Risks
- Diarrhea
- Increased susceptibility to GI infections
- Changes in bacterial populations
- Worsened NSAID-related intestinal injury when combined with NSAIDs
- Rebound gastric acid hypersecretion if stopped abruptly
When Combined With Other Drugs
- Certain antibiotics: altered absorption possibleons.
- Steroids (like prednisone): may increase diarrhea
- NSAIDs: may increase intestinal damage risk
Omeprazole for Dogs and Cats Warnings and Precautions
Keep the following safety points in mind when using omeprazole:
- Give before meals for best effect.
- Avoid long-term use unless directly prescribed.
- Do not stop abruptly; taper instead.
- Use caution when combining with steroids or NSAIDs.
- Watch for diarrhea or worsening GI signs.
- Pets with liver disease may need adjusted dosing.
Disclaimer: This information is for educational purposes only and should not replace professional veterinary advice. Always consult your veterinarian before using or combining any medications for your pet.
Frequently Asked Questions (FAQ)
Frequently Asked Questions
How fast does Omeprazole start working?
Most dogs experience improvement within
24–48 hours
, though ulcers require longer healing.
Should Omeprazole be given with food?
No. It works best when given
30–45 minutes before meals
.
Can Omeprazole be used long term?
Long-term use is possible but should be monitored due to microbiome and nutrient effects.
Does Omeprazole help with vomiting?
It may help
if vomiting is caused by acid irritation
, but it is not an anti-nausea drug.
Is twice-daily dosing better?
Yes. Research in dogs shows
better acid suppression
with
every-12-hour dosing
.

Editor
The Webvet Editorial Team is the in-house group of pet-care editors and writers behind Webvet, operated by Smart Pet Collective. The team researches, writes, and maintains Webvet's pet health, behavior, and medication content. Every article follows a defined editorial process: research from reputable veterinary and scientific sources, careful drafting, mandatory review of medical content by a credentialed veterinarian, and dated publication. Health and medication articles are medically reviewed by a licensed veterinary professional before they go live and are kept current over time.

Veterinarian · BVMS MRCVS
Dr. Pippa Elliott, BVMS, MRCVS, is a veterinarian with nearly 30 years of experience in companion animal practice. Dr. Elliott earned her Bachelor of Veterinary Medicine and Surgery from the University of Glasgow. She was also designated a Member of the Royal College of Veterinary Surgeons. Married with 2 grown-up kids, Dr. Elliott has a naughty Puggle named Poggle, 3 cats and a bearded dragon.



