my 7 month old choc lab has suddenly started drinking an awful lot of water, refusing to go to the toilet outside, dribbling a lot and has slight diaorrhea. I'm thinking an infection - any ideas anyone?

Take her to the vet. Nobody can diagnose anything without examining her - and speculating is pointless.

Especially if it's a bitch could be a pyo.

I agree get to the vets asap, she could have swallowed something and got it stuck or bloat better safe than sorry. Being a lab and how they are known for their appetite. Hope she/he is ok.

Louise