Glad to hear your little one is eating and drinking again. I just wanted to say that with my previous 19 year old pup, I found the syringe useful to feed water at times. Also, I found it useful to feed medication too - with tablets, I'd crush it and mix with water and squirt into her mouth (she was too smart and always spat the pill out, regardless of whatever medium I tried to hide it in
).
Hope he gets better really soon and back to his normal self!