Antibiotics work to resolve illness caused by bacterial infection. They are not effective against viruses, parasites, or fungal infections. Relying on them in incidences where they are not effective will not resolve illness, and antibiotics used unnecessarily can impair the immune system of your dog when they have a viral infection, which will impair the body's natural ability to fight the virus. Fungal and parasitic infections, such as yeast infections, can become worse when treated with antibiotics, as these medicines destroy some naturally occurring bacteria, resulting in an imbalance of natural, beneficial flora in your dog’s body, and allowing fungal organisms and parasites to flourish. Also, antibiotic use allows low levels of bacteria present to be exposed to the pharmaceutical and increases the chance that resistance to the medication will develop. If antibiotics are not useful in treating a viral or fungal infection, exposing bacteria to antibiotics unnecessarily and allowing resistance to build is taking an unnecessary risk.

Certain antibiotics are more effective on specific bacterial invasions and can be more appropriately used on bacterial infections in different locations of the body. Eye, ear, skin, pulmonary, and urinary tract infections respond differently to different antibiotics. Ensuring that bacterial infections are identified by conducting cultures of microorganisms present to confirm the presence of actual bacterial infection and to identify the type of bacteria involved will help ensure the correct antibiotic. Using the most appropriate medication will prevent the development of antibiotic resistance and will resolve conditions more effectively.

Side effects from antibiotics, including allergic reactions and compromise of the immune system in your dog, is possible with antibiotic use. Gastrointestinal disorders may develop from antibiotic use, as natural bacterial flora in the gut are destroyed by the antibiotic administered, impairing your dog's ability to digest food substances efficiently. Vomiting, diarrhea, and irritable bowel syndrome (IBS) can result. Pet owners can follow antibiotic use with probiotics and other supplements to restore gut flora functioning and counteract the effects of antibiotic use on “healthy” bacteria. Also, yeast infections are a common side effect of pharmaceutical use, as natural, “good,” bacteria are impaired, resulting in an imbalance in your dog's gut and on their skin surface. This can result in the overgrowth of yeast organisms and the development of a yeast infection from antibiotic usage. If allergic reactions develop, treatment with steroids or antihistamines may be necessary. Yeast infections can be treated with antifungal creams or oral medications. Antibiotic use can impair the ability of the body to produce and use nutrients such as vitamins and minerals. Vitamins A, B, magnesium, zinc and folic acid availability can all be decreased with the use of antibiotics.

It is necessary to use antibiotics as directed. Not completing or missing doses of medicine can result in resistance developing, as inadequate amounts of antibiotics are used to effectively destroy bacteria. Bacteria left behind may become resistant to the medication and subsequent treatments will be ineffective.

The most important things to know about antibiotic use in our dogs is when, why, and how to use them. It is important to establish that a bacterial infection indeed exists and what type of bacteria is present prior to determining if an antibiotic is necessary, and which antibiotic will be most effective. Antibiotics should always be taken as prescribed and directed by your veterinarian. Monitoring your dog's health for side effects and after effects of antibiotic use is important to address allergies, fungal infections, or other health issues that may result from use. Take appropriate steps to address these health conditions if they manifest.

Antibiotics have been of great benefit to us and our pets in resolving dangerous bacterial infections, but they are not without risks. Being aware of their appropriate use and possible negative effects that need to be addressed is important to maintain your dog's overall health and keep antibiotics an effective tool for the future.