Before you give it: is amoxicillin the right fit?
Amoxicillin is broad, but not right for every problem. A quick check first:
- Get a diagnosis first. Not every infection is bacterial, and not every bacterial infection responds to amoxicillin; a vet should confirm what’s going on.
- It’s broad, not universal. Amoxicillin covers a wide range of common bacterial infections, but does nothing for viruses and not every resistant bug — the vet matches it to the cause.
- Weigh your pet. The dose is set by body weight, so your vet needs an accurate weight to prescribe correctly.
- Mention any prior reaction. Tell your vet if your dog or cat has reacted to penicillin-type drugs before — amoxicillin is in that family.
What amoxicillin for dogs and cats is
Amoxicillin is an aminopenicillin (a beta-lactam), a broad, commonly used antibiotic1 prescribed for dogs and cats for a range of bacterial infections, including some skin, soft-tissue, and urinary infections.2 Whether it is the right choice, and at what dose, is a decision for the prescribing veterinarian — based on the specific infection, your pet’s weight and history, and what the vet finds appropriate.
We are a licensed veterinary pharmacy. We dispense what the vet prescribes3 — we do not diagnose or set doses — and we will tell you plainly when amoxicillin is not the right fit for your pet.
| Active ingredient | Amoxicillin |
|---|---|
| Strength | 250 mg or 500 mg per capsule |
| Also sold as | Amoxil |
| Drug class | Aminopenicillin (beta-lactam) |
| Form | Capsules in blister packs |
| Intended use | Dogs and cats only |
| Availability | Prescription, not for human use |
| Delivery to | All 50 US states, contact us for other countries |
Amoxicillin dosing for dogs and cats: your vet sets it
Amoxicillin for dogs and cats is dosed by body weight and set by your prescribing veterinarian, based on the infection, your pet’s weight, and their health history. We do not set doses, and this page does not list one. The label on your order reflects your prescribing vet’s instructions — follow it exactly and never adjust the dose yourself. Amoxicillin comes in 250 mg and 500 mg capsules; which strength fits your pet is part of what the vet decides.
Side effects to watch for
Most dogs and cats tolerate amoxicillin well. The most common effects are digestive — mild vomiting, diarrhea, or loss of appetite — and giving it with food often helps. Stop and call your vet if you see signs of an allergic reaction (facial swelling, hives, trouble breathing), severe or bloody diarrhea, or unusual lethargy. Tell your vet if your pet has reacted to penicillin-type drugs before, since amoxicillin is in that family.
⚠ Important safety notes
- Prescription medication. A veterinarian decides whether it’s appropriate and sets the dose — we never set one.
- Give it with food. This often eases the common digestive effects (mild vomiting, diarrhea, appetite loss).
- Watch for allergic signs. Facial swelling, hives, trouble breathing, severe or bloody diarrhea, or unusual lethargy — stop and call your vet.
- Penicillin family. Tell your vet about any prior penicillin-type reaction. For dogs and cats only; never dose a pet from a human or another species’ prescription.
Cost & how to get it
There is no public cart or online payment step. You place a reservation, a veterinarian reviews it and writes the prescription if it’s appropriate, then our pharmacy sends a secure payment link before anything ships — so the veterinary review costs you nothing separate, and you pay only for the medication. If amoxicillin isn’t right for your dog or cat, the order isn’t filled and you aren’t charged.
| Pack size | 250 mg | 500 mg |
|---|---|---|
| 30 capsules | $39.99 · $1.33/capsule | $45.99 · $1.53/capsule |
| 90 capsules MOST POPULAR | $89.99 · $1.00/capsule | $102.99 · $1.14/capsule |
| 200 capsules | $129.99 · $0.65/capsule | $148.99 · $0.74/capsule |
| 500 capsules BEST VALUE | $199.99 · $0.40/capsule | $229.99 · $0.46/capsule |
The 500 mg capsule costs a little more than the 250 mg at each pack size — your vet sets the strength your pet needs.
Related guides
Frequently asked questions
Do I need a prescription?
Yes — but you don’t have to arrange it yourself. A veterinarian reviews your order and prescribes it, then we dispense it legally. If it’s not right for your dog or cat, the order isn’t filled and you aren’t charged.
What is amoxicillin used for in dogs and cats?
It is a broad, commonly used antibiotic prescribed for a range of bacterial infections, including some skin, soft-tissue, and urinary infections. Whether it fits your pet is the prescribing vet’s decision.
What dose should I give?
We don’t provide dosing. The correct dose depends on your pet’s weight and condition and is set by the prescribing veterinarian. Follow the prescription exactly.
Is this the same as Amoxil?
Amoxil is a brand name for amoxicillin. This is the same active ingredient; brand and packaging may vary.
Do I get exactly what I see on this site?
We can’t guarantee a specific manufacturer. What you receive may look different, but the drug, strength, and ingredients are the same.
Medical disclaimer
This site is for informational purposes only and is not veterinary advice, diagnosis, or a treatment recommendation. A licensed veterinarian should determine medication selection, prescribing, dosing, and treatment for the individual animal. Never give a dog or cat antibiotics intended for another species; the wrong drug or dose can seriously harm your pet. All medications sold on this site are for animal use only and are not intended for human use or consumption.
Sources & References
- Merck Veterinary Manual, “Penicillins Use in Animals.” merckvetmanual.com (accessed 2026) Supports: amoxicillin is a semisynthetic broad-spectrum aminopenicillin active against many gram-positive and gram-negative bacteria.
- Weese JS, Blondeau J, Boothe D, et al. “ISCAID guidelines for the diagnosis and management of bacterial urinary tract infections in dogs and cats.” Vet J 2019;247:8–25. doi:10.1016/j.tvjl.2019.02.008; PMID 30971357. doi.org (2019) Supports: amoxicillin is a first-line empirical choice for sporadic bacterial cystitis (UTI) in dogs.
- FDA Center for Veterinary Medicine. Animal & Veterinary. fda.gov (accessed 2026) Supports: the prescription status of veterinary antibiotics.
