Hepatitis B and oral sex: what to know

Transmission is more concerning when blood is present, such as from bleeding gums, mouth sores, genital sores, or menstrual blood, or when skin is damaged. A person can have hepatitis B without knowing it, so a partner's appearance or lack of symptoms cannot establish safety. Oral sex is not the only possible route; sexual contact and shared items contaminated with blood can also matter.

If you are worried after contact, testing can clarify status. Hepatitis B may cause no symptoms, while fatigue or dark urine can occur in some people. See [Hepatitis B](/conditions/hepatitis-b/) and [Fatigue](/symptoms/fatigue/).

Ask partners about hepatitis B vaccination and use a condom or dental dam, especially when sores or bleeding are present. Do not share toothbrushes or razors. If a partner has hepatitis B, or you had a possible contact with infected blood or fluids, contact a clinician promptly about testing and post-exposure protection. [Hepatitis B Vaccination](/treatments/preventive-care-and-vaccination/hepatitis-b-vaccination/) is a key prevention option. A clinician may also arrange a [Liver Function Test](/treatments/diagnostics-and-screening/liver-function-test/) when appropriate.

Seek prompt advice after a known exposure, particularly if you are unvaccinated, pregnant, or unsure of your vaccination history. Arrange assessment for yellowing skin or eyes, dark urine, severe nausea, or unusual exhaustion. Urgent care is needed for confusion, fainting, or severe vomiting.

Ask: Was this contact a meaningful exposure? Do I need testing now or later? Am I vaccinated or protected? Does my partner need medical advice? What barrier method is suitable? What symptoms should prompt urgent care?