Can a penicillin shot cause yeast infection?

Penicillin is an antibiotic used to treat bacterial infection, while a yeast infection is fungal in nature. Antibiotics do not directly cause yeast infection. However, by disrupting the balance of microorganisms or killing sensitive bacteria in the body, they can create a favorable environment for the overgrowth of yeast, possibly leading to a yeast infection. Additionally, certain antibiotics can disrupt normal vaginal flora, increasing the risk of vaginal yeast infections in women.