ESP medical English jobs

Hello,

I am a medical student at a US medical school, but I'm currently on leave of absence, and am looking for an international experience during my time off. One thing I think I would be particularly well suited to would be teaching medical English: many of my friends have experience teaching basic English in Asia, which I think would be great, but I think with my medical background I'm uniquely qualified for teaching medical English. My question is, does anyone know a good resource for finding these jobs? I unfortunately don't have a TESL certificate, but would be willing to get one if it were not too much trouble.