2 very old ferals and topical flea treatment

[m935]

I had asked last year about how to deal with ear mites. I had treatments for my indoor cat who passed away that were drops for the inner ear. I tried many times. Both cats allow me to get close and pet them, but it became impossible to get the correct angel to get anything into the ear. PLUS, i feared getting something in the eyes or especially the food.
One really needs help over hte other. Since the fall, he doesnt shake his head as much.. but I assume he'll need help before the spring. Of course I dont even know if its ear mites. My question is.. should I get a treatment for fleas/ear mites and apply to the back of his neck? My fear is that both cats are at least 13 years old. I would hate myself forever if using frontline (or whatever) would "poison" them or make them ill in any way. I know some cats react badly. They have never had any chemical treatments, but it was horrible to watch him itch his ears last summer (even had a scar on back of ear - which I did treat with an ointment).
THANKS FOR ANY HELP

 

[fionasmom]

I have used the old Revolution formulation safely on cats. I do not use the new one specifically (Revolution Plus) because it contains sarolaner which is linked to neurological issues. No, I have not had any experience with any cat who had those problems, but just choose not to use it.

A couple of my outdoor ferals allow me to put the back of the neck type drops on them for flea prevention, but would never allow anything in their ears. I have not used any oral preps for this, but other may respond.