Don't wait. I noticed my cat, Max, drooling. I didn't know anything was wrong with him. But he was in kidney failure. I called the vet's office and they told me he was probably too hot. They thought that because he was also panting and vomiting. And they told me put him inside and cool him down. The next day I took him to the dr. I wish I had taken him when I found him, but I was following their advice. My cat lived from Friday until Monday. He got worse and we felt we had to let him go. I learned from my experience. When you notice ANYTHING AT ALL out of the ordinary about your cat, don't take ANY chances. GET IT TO THE VET ASAP. Lord, how I wish I had done that with Max. So go now, take your cat to the dr.