What is your favorite carpet/area rug cleaner for tough stains?

Resolve. They make a foam too. It's good.

Sprayaway glass cleaner
seriously, it works amazingly
Clothing, carpets, upholstery

I actually have a kitty who gets sick a lot too, using a tough carpet cleaner works wonders. Also hot water and dish soap if you care to

Natures miracle set in stain remover. Oxy formula. It’s pet safe and actually made to get rid of that kind of stuff. Works well

Simple Solution pet stain and odor removal. Works great.

Vinegar rubbed in with a Micro-fibre cloth...,

Enzyme cleaners break down organic stains.

Be careful when buying some of the cleaning shampoo etc. Some of them have "Opitical brighteners" which actually bleach or dye your carpet a violet color. And always remember to rinse with clean water to prevent leaving any detergent residue in the carpet. Then follow up with an antimicrobial. Like microban. Make sure to read all warnings!

I personally buy commercial carpet cleaner, but the best of the shelf would be Bissell promax clean carpet cleaning formula