Antibiotics

Antibiotics are medications that combat bacterial infections in dogs, either by killing bacteria directly or inhibiting their reproduction. Correct application determines success or failure. A dog with pyoderma needs entirely different active ingredients than one with a urinary tract infection, and the dosage is based on body weight.

Which antibiotic groups are used in dogs?

Penicillins form the basis of many treatments. Amoxicillin is almost always available in combination with clavulanic acid, and there is a reason for this: many bacteria have long developed resistance to pure amoxicillin. The combination neutralises these defence mechanisms.

Cephalexin from the cephalosporin group is particularly sought after for skin infections. Vets often reach for it first in cases of superficial pyoderma because it penetrates the skin well and has relatively few side effects.

Doxycycline from the tetracycline family is the treatment of choice for tick-borne diseases such as borreliosis or anaplasmosis. It accumulates in body cells and pursues bacteria even where they have hidden.

Fluoroquinolones (such as enrofloxacin) are considered reserve antibiotics for severe cases. They are only used when other active ingredients fail, or in serious conditions such as sepsis.

For which conditions does the vet administer antibiotics?

Skin infections top the list. A dog with hot spots or weeping eczema usually receives cephalexin, typically for 14 days. For deep pyoderma, treatment can extend to 6 to 8 weeks.

Urinary tract infections are treated differently depending on the pathogen. E. coli bacteria often respond to amoxicillin, whereas Pseudomonas infections require fluoroquinolones. The treatment duration is usually 7 to 14 days.

Respiratory tract infections require active ingredients that truly penetrate the lungs. Doxycycline or azithromycin achieve this better than many other antibiotics.

Vets treat dental infections and abscesses in the mouth with clindamycin. This antibiotic achieves high concentrations in bone tissue and is also effective against anaerobic bacteria that thrive in the absence of oxygen.

What happens with incorrect antibiotic administration?

The classic mistake: treatment is stopped as soon as the dog feels better again. Understandable, but dangerous. Visible symptoms often disappear before the bacteria are truly defeated. Surviving germs will be harder to combat next time.

Resistance also arises from underdosing. A 30 kg dog simply needs more active ingredient than a 10 kg dog, and not only in absolute amounts, but often also per kilogram of body weight.

Human antibiotics do not belong in a dog’s mouth. Some active ingredients are directly toxic to dogs, others come in completely wrong dosages. What helps a human can harm a dog.

How do you recognise side effects?

Diarrhoea is the most common side effect. Antibiotics hit not only harmful bacteria but also beneficial gut flora. Probiotics can counteract this – but please consult your vet first.

Loss of appetite and vomiting often indicate an irritated stomach lining. If the vet permits, it helps to give the antibiotic with food.

Allergic reactions manifest as swelling, hives, or breathing difficulties. These are emergency situations – go to the practice immediately.

How do you store antibiotics correctly?

Liquid antibiotics belong in the fridge, but not in the freezer. Cold preserves efficacy, frost destroys it. Tablets last at room temperature but need a dry place. The bathroom is out: too humid, too fluctuating.

Expired antibiotics go into special waste, not household waste and definitely not down the toilet. Residues end up in the environment via wastewater and further drive resistance development in pathogens.