I'm a un circumcised male with a yeast infection is it OK to masturbate?

What are you doing about your infection?

Everything is going to be sore and inflamed, but you can techniquely still masturbate. Might not be as satisfying as it usually is. You should treat the yeast infection ASAP.

Every time you shower, in order to avoid this, you must be diligent about pulling the foreskin back and washing underneath thoroughly.