Antibiotic Use In Veterinary Medicine: Side Effects and Safety Tips for Veterinarians and Owners
Sat, April 17, 2021

Antibiotic Use In Veterinary Medicine: Side Effects and Safety Tips for Veterinarians and Owners



Sharon M. Gwaltney-Brant, DVM, Ph.D., DABT, DABVT, of Veterinary Partner, a client education website, said that antibiotics are helpful in treating bacterial infections, eliminating invading bacteria without killing the surrounding cells. Antibiotics are manufactured from living organisms like fungi, as well as synthesized in a laboratory.

Each antibiotic is only effective on certain types of bacterial infections. Hence, choosing the appropriate product and using it at appropriate dosages depends on the type of infection and its severity. In veterinary medicine, some antibiotics that practitioners can use are penicillin, cephalosporin, cephamycin, and more. But sometimes, problems can arise when antibiotics are used inappropriately.


The Use and Impact of the Danish National Antibiotic Use Guidelines for Companion Animal Practitioners (2017)

151 companion animal practitioners completed the questionnaire, which corresponded to 17% of the DSAVA members (Danish Small Animal Association), said Lisbeth Rem Jessen and colleagues of biomedical and life sciences journal PMC. 30% of clinics had a written antibiotic policy. Among 151 participants, 96% said they had consulted the guidelines while 12% had never heard of the smartphone/tablet application. According to the authors, the guidelines are also available as downloadable PDF files in both Danish and English as a mobile/tablet application.

The recommendations are: using perioperative antibiotics in 0 to 10% of clean surgeries, treating superficial pyoderma with topical treatment alone or in conjunction with lincosamide, and treating cystitis using amoxicillin or potentiated sulfonamides. Of those who knew the application, 59% preferred the booklet or PDF format while 38% preferred the smartphone/tablet application. 3% said they had never used the guidelines or did not know which version they had used. The participants frequently consulted the recommendations on skin infections (78%) and UTI (64%). 

Between 73% and 92% said they followed the recommendations they had consulted. Overall, 65% (98 of 151 respondents) stated that the antibiotic guidelines had influenced their habits in one or more of the following: use of perioperative antibiotics, choice of treatment for pyoderma and/or UTI, and/or use of culture and susceptibility testing. 44% said that the guidelines prompted them to minimize their perioperative use of antibiotics. When asked about the respondents’ habits, 75% cited peri- or postoperative use of antibiotics in less than 10% of clean surgeries, which was in line with the recommendations cited by the study. Of the 70 participants who consulted the guideline recommendations on perioperative antibiotics (users), which was 81%. Of these, 69% did not consult the recommendations (non-users).

45% of respondents said that the guidelines had influenced their choice of treatment for canine superficial pyoderma. 65% said their first line of treatment for canine superficial pyoderma was topical treatment alone or in combination with systemic lincosamides. 70% of respondents consulted the recommendations on skin infections whereas 48% did not consult the recommendations. 24% of participants said that the guidelines influenced their treatment choice for UTI. 51% mentioned that they treat cystitis using amoxicillin or potentiated sulfonamides, in accordance with the recommendations. 59% consulted the recommendations on UTI (users) while 37% did not refer to the recommendations (non-users).



95% of participants fully agreed that the national Danish antibiotic use guidelines for companion animals are an important initiative. Further, 77% fully agreed that these can minimize the occurrence of antibiotic resistance in companion animals in Denmark. The barriers that prevent the respondents from adhering to the therapeutic recommendations were confidence in old prescribing practices (46%), unavailability of products registered for dogs and cats (34%), difficulties dosing the drug such as odd tablet size (31%), and costs. Other obstacles noted by the respondents were the lack of time for consulting the guidelines (25%), limited number of antibiotic drugs available on site (23%), owners experiencing difficulty administering the drugs (18%).


Are There Side Effects Associated With Antibiotics?

These vary from drug to drug. Generally speaking, side effects from the drugs tend to be uncommon and mild for pets. One known side effect in pets is vomiting and/or diarrhea, noted PDSA, the UK’s leading vet charity. For example, dogs undergoing treatment for Pseudomonas ear infections require high doses of enrofloxacin. When administered, dogs will most likely experience nausea. Sulfadimethoxine may cause the development of crystals or stones in urine in certain animals, whereas metronidazole leads to neurological side effects like staggering, dilated pupils, and seizures in cats. Animals can also develop allergic reactions to antibiotics resulting in severe skin reactions, collapse or shock, and low blood pressure. Fortunately, severe reactions are rare.



How Do I Use Antibiotics Safely?

Watch out for superbugs! Superbugs refer to groups of bacteria that became resistant to antibiotics and can survive even if they are treated with antibiotics. Antibiotic resistance is dangerous for both practitioners and owners, you and your veterinarian may find it difficult to fight off future infections.

The more antibiotics are administered to your pet, the more the drugs create more resistance. As an owner, you can reduce the risk of resistance by prescribing the right antibiotic for the right duration. Avoid giving antibiotics to your pet if it’s not needed. Administer the correct dose at the right time and complete the course of the treatment plan, regardless if your pet appears better. Don’t skip a dose or save the drug for later use, emphasized AVMA (American Veterinary Medical Association), a not-for-profit association founded in 1863. If you missed a dose, this will depend on the drug and the infection being treated. In most cases, you can wait and administer the antibiotic again at the scheduled time.

Check if the antibiotic comes with a pharmacy sheet. A pharmacy sheet will provide you with instructions on what to do if you miss a dose. If the drug does not come with the instructions, you may contact the provider or manufacturer. Don’t increase the dosage to make up for missed one, as it may contribute to side effects.

Don’t give your pet any antibiotics unless prescribed by your veterinarian. Giving the wrong antibiotic for the wrong condition may cause more harm than good to your pet. You can remove leftover antibiotics by taking them to your veterinarian. It is not advisable to dispose of the antibiotics to the environment as this creates resistance. Feel free to discuss with your veterinarian about the responsible use of antibiotics and antimicrobials to safeguard your pet’s health. Your veterinarian will gauge when and if your pets need treatment with antimicrobials.


Antibiotics should be used rationally by both veterinarians and owners. Owners should not miss any doses and increase the dosage for missed doses. Allergic reactions may occur, but severe cases are rare for pets.