Certain types of antibiotics for animals are available at pet stores or online without a prescription. Some topical antibiotic ointments for humans could possibly be used safely on dogs, it's always best to get over the counter antibiotics for dogs so you don't end up making your pup sicker. Neosporin, a topical antibiotic for humans, has ingredients that have been approved for use in pets, but one ingredient is a problem for dogs.
Topical antibiotics aren't always safe
You might think there's nothing wrong with rubbing a little topical antibiotic ointment on your pet's wound. Topical antibiotics such as bacitracin and polymyxin B — two of the main ingredients in the topical salve Neosporin — have been approved for use in pets.
The third ingredient, neomycin, has been associated with hearing loss in dogs. The lubricant used to deliver the medications can also cause digestive upset if your pup happens to reach the spot and lick it off, resulting in vomiting or diarrhea, according to the American Kennel Club.
Topical antibiotics containing zinc are also dangerous to your dog, according to the University of Connecticut School of Pharmacy. Avoid over the counter antibiotics for dogs such as bacitracin zinc or other zinc products like diaper rash ointments.
Dog antibiotics without a vet
Although systemic veterinary antibiotics are available without a prescription in feed stores and pet stores for livestock and fish, you usually need a vet's prescription for dogs even if you buy them online. Should you choose to buy dog antibiotics without a vet prescription from an online source, you have no guarantee of the product's effectiveness or that it is correct for your dog's illness.
It's easy to think that a round of penicillin will take care of about anything that ails your pet. However, the antibiotic would be inappropriate, for example, for a staph infection, per the University of Minnesota. Staph produces beta-lactamase, which Merriam-Webster's dictionary describes as an enzyme that inhibits the effective action of penicillin by hydrolyzing it.
To effectively choose an antibiotic for your dog, you'd need to be able to discern what type of bacteria is making your dog ill. Each bacterial infection requires antibiotic treatment for a specific length of time. To treat an infection that would require 7 weeks of antibiotics for fewer weeks — or with the wrong type of antibiotic for the infection — could put your pet's health at serious risk.
Side effects of antibiotics usually include diarrhea and vomiting. Not only could you end up with unnecessary messes to clean up, but your dog could also end up worse off due to dehydration.
Veterinary antibiotics OTC
Penicillin is one example of an antibiotic that's available over the counter at feed stores for several species such as cattle, swine, and fish. However, the Food and Drug Administration (FDA) hasn't approved the drug — or any antibiotics that are injected or ingested — for companion animals such as dogs.
Because directions for safe and effective use of penicillin or other antibiotics by a layperson can't be written to apply to all circumstances, the FDA requires antibiotics for dogs to come with a prescription. This enables the vet to write specific directions for each animal based on their individual needs such as the type of infection, duration of administering the drug, weight, species, and other factors.
An antibiotic that works on cattle, swine, or fish won't necessarily work for your dog, even if it appears to be a name such as "penicillin" that you're familiar with. Formulations for each species are geared toward bioavailability in that particular type of animal's system. A formulation for an herbivore or ruminant won't work the same in a meat-eating non-ruminant animal, for example, according to the University of Connecticut.
Bottom line: Don't use fish or livestock antibiotics on your dog. To do so could create bacterial resistance to treatment in the future, delay or pet's recovery, or even endanger its life.
- American Kennel Club: Can You Use Neosporin on Dogs?
- University of Connecticut School of Pharmacy: Patient Safety When the Patient is a Companion Animal
- The University of Minnesota: Canine Pyoderma
- Merriam-Webster Dictionary: Beta-lactamase
- Food & Drug Administration: FDA Regulation of Animal Drugs
- Animal Poison Control Center