Dr. Lizzy is a practitioner of alternative pet care.
When Steve's new dog Kisses is horribly crushed, leaving Stan heartbroken in "Stan's Best Friend", he seeks out Dr. Lizzy in desperation after seeing a flyer of her breastfeeding a monkey at the library. Dr. Lizzy brings Kisses back to life, but creates a monster in the process--sewing his eyes where his testicles used to be, giving him one frog's leg and one raw chicken drumstick, sewing a softball mitt to his skull, and replacing his lungs with cumbersome machinery. She also repairs Stan's car, turning it too into a mechanical patchwork monstrosity, and charges him $6000.
Dr. Lizzy is voiced by Amy Sedaris.