Help! My Dog Licks Pus: Why They Do It & What To Do About It
Why does my dog lick pus?
A dog might lick its wounds for the same reason you might grab your own sore spots, the nerve activation from the rubbing sensation is theorized to diminish the feeling of pain. Canine saliva also has some antibacterial properties against E. Coli and Streptococcus canis and contains histatins that can ward off infection. There is evidence that licked wounds heal twice as fast as unlicked wounds. Licking is one of the few tools your dog has to address (and communicate) their issues and keep themselves clean from debris.
Dogs use their mouths, and particularly licking, for all sorts of things such as grooming, bonding, soothing, or expressing themselves. Your dog might lick you for any number of reasons. Canines in the wild actually lick their mothers muzzles to encourage them to regurgitate their meal. They may also lick because you taste nice, to show affection, or as a sign of submission. In summary a dog has many many reasons to lick itself and you regardless of whether or not pus is involved.

A dog may lick their wounds (or the wounds of others) regardless of whether it has pus or other things that we as humans might deem gross. It’s unlikely your dog is licking its own pus or wounds for its own sake.
Should I let my dog lick pus?
No, despite the fact that canine saliva can be helpful in some cases, your dog licking their wounds is likely not the best way to deal with wounds. Most dogs will excessively lick their wounds which can cause irritation and can lead to an infection from the bacteria in their mouths or the environment. Seeking veterinary assistance, washing and using a proper antibacterial solution and covering the wound with a bandage are likely better choices.
You also shouldn’t let your dog lick your wounds either. Dogs' mouths contain around 400 different kinds of bacteria, many of which are different from the bacteria you usually have in your body. A study showed that only 16.4% of bacteria are shared between you and your dog. Letting your dog lick a wound on your body has the potential to do harm.
That being said if your dog does lick a wound or some pus it is unlikely to do a lot of harm. It is just best to prevent that from happening.
What to do about my dog licking pus?
Properly bandaging the infected area is likely the best solution. This will also help the wound heal quicker and prevent it from reopening. If your dog is constantly licking a wound on itself, pulling at the bandage (or sutures in the case of a surgery) you may wish to use a standard cone to prevent them from licking. There are also sprays that contain bitter tastes to discourage licking, however that is unlikely to be a reliable way to discourage a dog in pain from licking itself in the case of your dog experiencing pain from a wound.

In addition there are also inflatable pet collars, which can be better than cones which can hurt your dog if they jump up or down from furniture or prevent them from eating or doing other normal activities. Specialized dog clothing, recovery suits, socks, or a professionally applied wound dressing are all options to protect your dog from licking their wounds and any pus that may be on them.
When should I be worried about dog licking?
If your dog is showing signs of pain such as shaking, flattened ears, aggression, panting, crying, or whining, limping, loss of appetite, excessive licking, etc. then seek veterinary assistance, especially if you are unable to identify the cause of the problem or the problem persists or becomes a health risk.
Licking is a normal activity that dogs will do to groom themselves and excessive licking is to be interpreted relative to how much your dog licks themselves normally. If you notice signs of redness, inflammation, or pus then you should take that as a sign to investigate further and treat a potential wound or seek veterinary assistance. Your dog will thank you for it!
