Proton pump inhibitor · For Dogs

Omeprazole dosage reference for dogs (Prilosec)

This page's standard weight-based reference is 1 mg per kg (0.45 mg per lb), with Once or twice daily recorded as the reference frequency. Use the calculator to see the arithmetic for your dog's weight, then confirm the indication, product, and actual dose with a veterinarian.

Onset: 1-2 hours; full acid suppression in 3-5 days
Duration: 24 hours per dose
Class: Proton pump inhibitor

Weight-based calculator estimate from the references listed on this page. This page has not been independently DVM-reviewed — see our methodology .

This information is for educational purposes only. Always consult your veterinarian before giving medication to your pet. Do not use this calculator for emergencies, overdoses, pregnancy, very young animals, very old animals, pets with liver/kidney disease, or pets taking multiple medications.

Each medication page lists the references recorded for its data. The calculator math and editorial presentation are maintained by PetDosageChart; a page is independently DVM-reviewed only when a named reviewer byline appears. See our methodology and limitations.

Omeprazole (often known by brand names such as Prilosec and GastroGard) is a proton pump inhibitor commonly used in veterinary medicine for Stomach ulcers, Gastroesophageal acid reflux, Esophagitis, NSAID-induced gastric erosion, and Helicobacter gastritis. Understanding the correct dosage, administration, and potential side effects of Omeprazole is critical for your dog’s safety and well-being.

A typical Omeprazole dose for dogs is around 1 mg/kg Once or twice daily, within a usual range of 0.5-1.5 mg/kg. Available forms include Tablet, Capsule, and Oral paste.

Calculator Warning: Use this only as an educational estimate. Your veterinarian may prescribe a different dose based on your pet’s condition, age, weight, other medications, and medical history.

Omeprazole Dosage Calculator for Dogs

Enter your dog’s weight below to estimate the Omeprazole dose from the 1 mg/kg guideline. Your veterinarian may adjust it for your dog’s age, condition, and other medications, so treat the result as an educational starting point, not a prescription.

Dosage Calculator · 01

Enter your dog's weight

Quick Dosage Chart

Typical Omeprazole amounts for common dog weights, for quick reference:

Dosage Chart · 02

Prilosec weight-based reference chart for dogs

Scroll sideways to see full table

Weight	Lower Reference	Standard Reference	Upper Reference	Frequency
5 lbs (2.3 kg)	1.1 mg	2.3 mg	3.4 mg	Once or twice daily
10 lbs (4.5 kg)	2.3 mg	4.5 mg	6.8 mg	Once or twice daily
15 lbs (6.8 kg)	3.4 mg	6.8 mg	10.2 mg (10mg tablet)	Once or twice daily
20 lbs (9.1 kg)	4.5 mg	9.1 mg (10mg tablet)	13.6 mg	Once or twice daily
25 lbs (11.3 kg)	5.7 mg	11.3 mg (10mg tablet)	17.0 mg	Once or twice daily
30 lbs (13.6 kg)	6.8 mg	13.6 mg	20.4 mg (2 × 10mg)	Once or twice daily
40 lbs (18.1 kg)	9.1 mg (10mg tablet)	18.1 mg (2 × 10mg)	27.2 mg	Once or twice daily
50 lbs (22.7 kg)	11.3 mg (10mg tablet)	22.7 mg	34.0 mg	Once or twice daily
60 lbs (27.2 kg)	13.6 mg	27.2 mg	40.8 mg (4 × 10mg)	Once or twice daily
70 lbs (31.7 kg)	15.8 mg	31.7 mg (3 × 10mg)	47.5 mg (5 × 10mg)	Once or twice daily
80 lbs (36.3 kg)	18.1 mg (2 × 10mg)	36.3 mg	54.4 mg	Once or twice daily
90 lbs (40.8 kg)	20.4 mg (2 × 10mg)	40.8 mg (4 × 10mg)	61.2 mg (6 × 10mg)	Once or twice daily
100 lbs (45.4 kg)	22.7 mg	45.4 mg	68.1 mg (7 × 10mg)	Once or twice daily
120 lbs (54.4 kg)	27.2 mg	54.4 mg	81.6 mg (8 × 10mg)	Once or twice daily
150 lbs (68 kg)	34.0 mg	68.0 mg (7 × 10mg)	102.0 mg (10 × 10mg)	Once or twice daily

Parenthetical tablet amounts are arithmetic comparisons only. They do not account for scoring, release type, concentration, product labeling, or whether this medication is appropriate for an individual animal.

By Weight

Prilosec reference by dog weight

Choose a common weight to open its optional reference page. Use the main medication calculator for a different exact weight.

Common-weight pages are convenience views of the same educational reference, not separate medical recommendations.

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How to Give Omeprazole to Your Dog

Give omeprazole by mouth on an empty stomach, 30-60 minutes before feeding. Do not crush or break enteric-coated tablets or open capsules, as the coating protects the drug from stomach acid. If your dog needs a smaller dose, ask your vet about compounded formulations. Administer at the same time each day for best results.

It may interact with Reduces absorption of ketoconazole and itraconazole (need acid for absorption), May increase effects of diazepam and phenytoin, Sucralfate should be given separately (2 hours apart), and May alter absorption of iron supplements.

Side Effects and Safety

Common side effects include Diarrhea, Decreased appetite, Mild nausea, and Gas or flatulence. More serious side effects can occur, such as Vitamin B12 deficiency with prolonged use, Rebound acid hypersecretion on abrupt discontinuation, Hypomagnesemia with long-term use, and Increased risk of GI infections.

Cautions · 12

When Prilosec should be used with caution or avoided

Some dogs should not take Prilosec, or need a different dose and closer monitoring. Tell your veterinarian about your pet's full health history and every other medication or supplement they take before giving Prilosec.

Known hypersensitivity to proton pump inhibitors
Concurrent use with atazanavir or nelfinavir

Interactions · 13

Prilosec drug interactions

Prilosec can interact with other drugs. This list is not complete — always give your veterinarian a full list of your dog's medications and supplements.

Reduces absorption of ketoconazole and itraconazole (need acid for absorption)

May increase effects of diazepam and phenytoin

Sucralfate should be given separately (2 hours apart)

May alter absorption of iron supplements

Calculator Limits · 14

When not to use this calculator

This calculator gives a general educational estimate for a healthy adult dog at a known weight. Do not rely on it in these situations — talk to your veterinarian instead:

In an emergency, or after accidental ingestion or a suspected overdose
For pregnant or nursing pets
For very young or very old dogs
For pets with liver disease, kidney disease, or another chronic illness
For pets taking several medications at once
When you are not sure of your dog's current, accurate weight
For combination products that contain additional active ingredients

Overdose · 15

Suspected overdose: what to do

If you think your dog had too much Prilosec, or swallowed any medication by accident, act right away. Do not wait for symptoms to appear.

Call your veterinarian or the nearest emergency animal hospital.
ASPCA Animal Poison Control Center: (888) 426-4435
Pet Poison Helpline: (855) 764-7661

A consultation fee may apply to the poison hotlines. Have the medication packaging ready, and note how much your pet may have taken and when. Do not try to make your pet vomit unless a veterinarian tells you to.

When to Call the Vet

If your dog experiences any of the following, contact your veterinarian or an emergency clinic immediately:

Vomiting blood or dark coffee-ground-like material
Black, tarry stools indicating GI bleeding
Persistent vomiting despite medication
Complete loss of appetite lasting more than 2 days
Weakness, pale gums, or signs of dehydration

Frequently Asked Questions

Frequently Asked · 07

Questions about this medication

Should omeprazole be given on an empty stomach to dogs?

Yes, omeprazole is most effective when given on an empty stomach, ideally 30-60 minutes before the first meal of the day. This allows the drug to be absorbed and begin blocking acid pumps before food stimulates acid production.

How long can a dog take omeprazole?

Omeprazole is typically prescribed for 2-8 weeks depending on the condition. Long-term use beyond 8 weeks should be under close veterinary supervision due to potential nutrient absorption issues. Your vet may taper the dose rather than stopping abruptly to avoid rebound acid secretion.

Can I give my dog human omeprazole?

Many veterinarians prescribe human OTC omeprazole for dogs at appropriate doses. However, do not use formulations containing additional active ingredients (like combination heartburn products). Always confirm the appropriate dose with your veterinarian.

What are signs of stomach ulcers in dogs?

Signs include vomiting (sometimes with blood), dark tarry stools, loss of appetite, weight loss, abdominal pain, and lethargy. If you notice any of these, especially dark stools or bloody vomit, seek veterinary care immediately as ulcers can be serious.

Can omeprazole be used alongside NSAIDs in dogs?

Yes, omeprazole is commonly used as a gastroprotectant alongside NSAID therapy to help prevent NSAID-induced stomach ulcers and gastric erosion. This combination is particularly recommended for dogs on long-term NSAID use or those with a history of GI sensitivity.

Use This Guide Safely · 08

What weight alone cannot tell you

The calculator performs one narrow job: it multiplies your dog's weight by the lower, standard, and upper mg/kg values recorded for Prilosec. It cannot decide whether this drug, indication, formulation, or schedule is appropriate for an individual animal.

Context in this medication record

Commonly listed uses: Stomach ulcers, Gastroesophageal acid reflux, Esophagitis, NSAID-induced gastric erosion, Helicobacter gastritis
Recorded forms: Tablet, Capsule, Oral paste
Reference timing: Once or twice daily; onset 1-2 hours; full acid suppression in 3-5 days; duration 24 hours per dose

Individual checks a calculator cannot perform

Confirm the diagnosis and the reason this medication is being considered.
Match the exact product, concentration, route, and whether a tablet may be split.
Account for age, pregnancy, organ function, genetics, allergies, and prior reactions.
Review every prescription, over-the-counter product, and supplement your pet takes.

Recorded cautions

Known hypersensitivity to proton pump inhibitors; Concurrent use with atazanavir or nelfinavir.

Recorded interactions

Reduces absorption of ketoconazole and itraconazole (need acid for absorption); May increase effects of diazepam and phenytoin; Sucralfate should be given separately (2 hours apart); May alter absorption of iron supplements.

These lists reproduce the structured record used by this page and may not be exhaustive. Show your veterinarian the product label and your dog's complete medication list before acting on a number.

Related · 08

Related medications for dogs

Sources · 09

Sources & references

The structured medication record behind this page names the references below. The links open the publisher or official resource; they do not turn this page into a prescription for an individual animal.

Plumb's Veterinary Drug Handbook — listed in this medication's source record.
Merck Veterinary Manual — listed in this medication's source record.
DailyMed label search for Omeprazole — check current product and formulation labels; some veterinary uses may be off-label.

Source names are shown at the record level; passage-level page and label citations are still being added. Read our methodology and limitations.

Transparency · 11

How this page was made

This page's structured medication record includes Plumb's Veterinary Drug Handbook among its source names. PetDosageChart applies the record's mg/kg values to the entered weight and presents the arithmetic result. A source record is not the same as an individualized prescription or an independent clinical review.

Sources cited: Plumb's Veterinary Drug Handbook
Merck Veterinary Manual
Calculator formula: Doses scale linearly from a standard basis of 1 mg per kg (0.45 mg per lb) of body weight, given Once or twice daily. The calculator multiplies that basis by your dog's weight and shows an arithmetic comparison with recorded tablet sizes. That comparison does not determine whether a tablet is scored, splittable, or appropriate for your pet.
Editorial owner: Prepared and maintained by the PetDosageChart editorial team, a software-led publisher and not a veterinary practice.
DVM review status: Not independently DVM-reviewed. A named reviewer and review date appear here only after a confirmed review.

More on our methodology and editorial process — how we source, calculate, and review dogs dosage data.

Safety · 10

More resources

Pet Medication Safety Hub — What's safe, what's dangerous, and emergency signs
How we calculate dosages — Our sources, math, and review process
Printable emergency checklist — One-page reference for your fridge or first aid kit