The updated ISCAID antimicrobial use guidelines for canine pyoderma have just been published (Loeffler et al. Vet Derm 2025). This is the first major update since the guidelines were first published in 2014. The document is a bit of a monster, so I’ll break down some of the key points in my next few posts.

Let’s start with the guidelines for treating surface pyoderma, which includes pyotraumatic dermatitis (aka acute moist dermatitis aka “hot spots”), intertrigo (skin fold dermatitis) and bacterial overgrowth syndrome, each of which is pictured below:

A big advantage of treating skin is that it’s on the outside of the animal. We can treat superficial infections topically, and that can be a lot easier, safer and more effective than systemic treatments, and lets us save systemic antimicrobials (e.g. oral or injectable) for when we absolutely need them. This simple figure sums it up nicely: if it’s surface or superficial pyoderma, we want to treat topically if at all possible. We can’t always do that, but if the patient and owner are amenable to it, that’s the recommendation..

Here are the main treatment recommendations from the new guidelines. For full details, as well as information about diagnosis and other issues, check out the complete document.

  • Topical antimicrobial therapy is the treatment-­of-choice for surface pyoderma. The first option is 2-4% chlorhexidine. It’s the most proven treatment and is readily available.
  • A combination of topical antimicrobial therapy with topical glucocorticoids or with a short course (5–7 days) of systemic glucocorticoids (at anti-inflammatory doses) or antipruritic medication may be helpful in cases of pyotraumatic dermatitis or intertrigo where an inflammatory or pruritic primary cause is involved.
    • Dose is the key. Corticosteroids like prednisone can be a great help with treating certain infectious diseases, since inflammation is often what’s driving disease. We just need to make sure we stick with anti-inflammatory doses, not immunosuppressive doses.
  • Antiseptic treatment can be continued proactively on previously affected skin, potentially life-­long, where the primary underlying causes cannot be resolved (e.g. skin folds) and the risk of recurrence remains.

Here are a couple of case examples from the guidelines:

The next post will be the big one on superficial folliculitis. Stay tuned.