Hepatitis B in adults: symptoms, testing, and prevention

Hepatitis B is a viral infection that can inflame the liver. It can spread through infected blood or body fluids, including sexual contact, shared needles, unsterile equipment, or transmission around birth. An adult may feel completely well, or develop fatigue, nausea, poor appetite, joint aches, dark urine, or yellowing of the eyes. Symptoms do not show how long infection has been present.

Testing usually uses a group of blood markers rather than one result. These markers can help distinguish current infection, past exposure, and immunity from vaccination. A clinician may also request a liver function test and discuss medicines, alcohol, other conditions, and follow-up. Results guide whether monitoring, treatment, or advice for close contacts is needed.

Ask about testing if you were born in or have lived in a region where hepatitis B is common, have a household or sexual contact with the infection, work around blood, are pregnant, or have had possible exposure. Check your vaccination history and discuss vaccination if you are not protected. Do not share razors, toothbrushes, needles, or injecting equipment, and use condoms until a clinician explains your status and your partner's protection.

Book medical advice promptly for new yellow eyes, dark urine, persistent fatigue, nausea, or pain under the right ribs, particularly after a possible exposure. Seek urgent care for confusion, severe vomiting, severe abdominal pain, unusual bleeding, or rapidly worsening jaundice. After a recent exposure, prompt advice matters because preventive steps may be time-sensitive.

Ask which hepatitis B tests you need, whether your liver function test is appropriate, whether vaccination is recommended, and whether household or sexual contacts need testing. If a result is positive, ask what it means, how follow-up will work, and which medicines or supplements to avoid.