Will Falconer, DVM Moderator
Great experiment in the neurotoxic flea meds, Mclark! Bravo! And I applaud your decision not to buy the "due" rabies vaccine -- that would be a disaster to a dog like this and could spell his decline.
For more on seniors and rabies (or any!) vaccines, see this post: https://vitalanimal.com/stop-vaccinating-seniors/ Far more risk than need to vaccinate a senior. Vet immunologists recognize this and have for decades. Seniors don't die of parvo or distemper or hepatitis!