How can I tell if I have an STI of the mouth?

If you’ve given oral sex to someone with an STI, it’s possible that it can spread to your mouth. Things like gonorrhea, herpes and HPV can all pass from genitals to the oral cavity. Gonorrhea might feel like a sore throat or swollen lymph nodes. Herpes can be spread whether or not someone has an active flare, and it causes painful sores. HPV can lead to oral and throat cancers. Protect yourself with frequent testing (both you and your partners), vaccination against HPV and barrier protection (condoms and dental dams).