My 15 year old dog wakes up frequently at night, doesn't want to eat or go out to potty, just whines and barks till I am up, can I give him benadryl to sleep?

No. Call your vet for advice on what to do.

If your dog is in pain, it might be time to say goodbye.

There are some natural relaxers out there, but I would never advise you to give them until you spoke with your vet. Valerian root is one, and there are some great natural recipes for sleep aids for your dog. But again, it sounds like your dog is trying to tell you something , and only a Vet can tell you what is wrong.

Bendedryl may not help him sleep unless he was suffering from an allergy, but once your vet checks him, they may give you the okay to give him an Aspirin if he is in pain. It is crucial to get vet clearance before giving any human meds. Dogs with heart issues should never take Aspirin.

15 is an old dog... he may be telling you something.