Thanks for the information. To start with, from what you desribe, I think your cat has a saddle thrombus. This is usually due to heart problems in cats. With that being said, the enlarged heart could just be an incidental finding. It is possible this could be a back problem as well. If this is a saddle thrombus, heparin is the most common drug used by vets to treats this disease. It doesn't treat the existing clot but prevents other clots. Enteric coated aspirin can be used to treat this as well. Usually, the dose is 81mg every 2-3 days. I would be very careful giving aspirin to a cat, though. It could be toxic to cats and bleeding complications could arise. I wouldn't recommend giving aspirin without any pre treatment bloodwork either. It can worsen any pre-existing liver, kidney or platelet (clotting) disorders. Other drugs that can be used are butorphenol for pain, acepromazine for vessel dilation or warfarin (used in humans, not really studied well in cats). The heart disease needs to be treated as well. Please let me know if you have any other questions. Hope this helps.

Ant or roach killer toxicity would most likely not cause paralysis like this. He would have to ingest large amounts of it. Neurotoxicity is a possibility, but it would act more on the central nervous system most likely, possibly creating depression, seizures, increased salivation or incoordination. Not a very common toxicity in cats at all. Don't think I have ever seen it at least.

Great! Sounds like he is making progress. Give him time; hopefully the dragging of the paw will resolve also. If he continues it, you may want to get a bootie to put on his paw, so he doesn't rub a sore on the top of the foot from dragging it.