Why are my cats drooling brown, not eating, lethargic, smelly? Is it contagious?

He could have an upper respiratory infection, dental problem, or other medical issue. It is impossible to know the cause without doing an examination. If he has an upper respiratory infection, it could be contagious to the other outside cats. Make sure you wash your hands and change clothing after handling him before touching your indoor cats. If possible, catch him and take him to a vet for an examine and treatment.

It’s quite possible, cats can be really sensitive to scents. If they both started drooling at the same time, then I would suspect an environmental cause. So a strong scent, or something they could have licked or eaten. Some houseplants will cause drooling. You can rinse their mouths out with water to help, but if it doesn’t improve in 24 hours, they should get checked out by a vet.

I would be most suspicious of a calicivirus infection causing these signs. Calicivirus is a vaccine preventable disease that is mostly seen with kittens. This virus will cause ulcers in the mouth, which will cause it to bleed a little. This disease is often self-limiting, but can cause severe ulcers in certain cases, so it will definitely be good for the vet to check them in the next day or two. It's likely not an emergency though, so they should be fine to wait until then. I hope that helps and all is well with the cats.

It sounds like your vet diagnosed her with an upper respiratory infection. Depending on the virus that causes this, the signs can appear in the eyes, nose or mouth. There is a virus called calicivirus that can cause sneezing and ulcers in the mouth. These can be quite painful and make the cat not want to eat. I typically recommend feeding a canned diet so she can lap it up rather than chew it. A/D is a good diet for this. It is made by Hill's and is available by prescription through a veterinarian. I also will sometimes prescribe pain medication to keep them comfortable and eating while they have ulcers in their mouths. I would recommend calling your veterinarian in the morning to discuss these things. We don't want her to go too long without eating.

Cats can develop something called gingivostomatitis as well as feline oral resoptive lesions. These are both very painful and require antibiotics and sometimes steroids as well as dental procedures to correct. Also if there's any possibility she chewed something like electric cord or plant that can calls the signs as well. I recommend Dusk be checked out by a veterinarian as soon as possible. This is to prevent her from becoming dehydrated and malnourished from not eating. Do not give her any human medications as they are very toxic to cats and I'll make the situation worse.

If all four are experiencing the same symptoms, I would be suspicious that they have eaten something toxic that has upset their stomach (drooling is a sign of nausea), and the voice change could be due to vomiting that you may have not seen. Cats like to chew on plants, and oftentimes, there are plants around the house and yard that are toxic to cats, but the owners do not know they are toxic. They also could have eaten an insect or some rotten food that is causing their symptoms. Given that all four are showing these symptoms, I would check any plants in the house and yard (if they are allowed outside) for toxic plants, and remove them. Given they are still eating, I would monitor them for now, and if the drooling and voice changes continue over the next 24-48 hours, I would take them all into the vet for an exam.

Drooling and lethargy generally indicate an upset stomach and are signs you should pay attention to. She's likely not drinking because her stomach is upset. If she is not drinking, I recommend to get her into the vet as soon as you can. Cats can dehydrate fairly quickly and this will only make her feel worse. There are many things that can cause her stomach to be upset. Its impossible to say for sure if it's related to the kittens but they could certainly transmit a virus or intestinal parasite to Cupcake. I hope this helps and that she starts feeling better!