Hi!
I don't know anything about sore doggy armpits but I do know about salt water. salt water used to cure or help skin problems should only be 1% salt, which is about a quarter of a teaspoon in a mug of water. It should also be either sea salt or rock salt as table salts have added ingredients to preserve etc(just read the packaging, ingredients need to be 100% salt).

You can buy it already mixed, 'saline solution'. NOT the one for contact lenses though as it usually contains other ingredients too. Best place to find it as pure saline solution is piercing shops/online piercing jewellery shops. bodyjewelleryshop is one. It is more expensive but the solution is perfect mix.Too much salt, even 2% is too harsh on the skin.

Might be worth asking your vet if paw wax can be used to protect the armpit area too. Just a thought as its water proof too so may be better for long term results

Hope it clears up soon, poor fur baby

Seasalt has slightly different properties & is much more effective than tablesalt

Nettle wash (tea) - using only fresh young (top ) leaves can also be effective. Collect a bunch of leaves, wash, put in large saucepan with some waTer & simmer until cooked which doesnt take very long. Drain liquid & allow to cool. & then use to bath effective areas.

Hello Lynne do you know why your dog has sores under the legs, are you saying it is the result of swimming?
If so best to treat the cause rather than the symptoms so I would apply something like a barrier cream to the dry skin before your dog goes in the water
Maybe sudacream or vasaline.