Acute hepatitis B infection: what to know

Some people feel well, while others develop tiredness, poor appetite, nausea, discomfort on the upper right side of the abdomen, dark urine, pale stools, joint aches, fever, or yellowing of the skin and eyes. Symptoms alone cannot confirm the infection; blood tests are used to identify hepatitis B and assess its effect on the liver.

“Acute” describes the early phase after hepatitis B virus infection. It is different from chronic hepatitis B, in which the virus remains in the body beyond the acute phase. Follow-up testing shows whether the infection has cleared or continues and checks whether the liver is inflamed or struggling to work normally.

The virus spreads through infected blood and certain body fluids. Possible routes include sexual contact, sharing needles or equipment that may carry blood, needlestick exposure, and transmission during childbirth. It does not spread through ordinary contact such as sharing a room, talking, coughing, or hugging.

A lasting hepatitis B infection can injure the liver over time and is linked with cirrhosis and liver cancer. That long-term risk is why completing follow-up matters even when early symptoms settle.

Arrange clinical assessment and attend every planned blood test. The clinician may check markers of the virus, liver enzymes, bilirubin, and how well the blood clots. Most care focuses on rest, fluids, adequate food, symptom control, and monitoring. Severe liver inflammation or impaired liver function may require hospital care and specialist-directed antiviral treatment.

Avoid alcohol and do not start herbal products, supplements, or non-prescription medicines without checking whether they are safe for your liver. Tell any clinician treating you that you have acute hepatitis B so medicine choices can be reviewed.

Until a clinician confirms that transmission precautions can stop, use condoms, cover cuts, and never share needles, razors, toothbrushes, glucose-testing equipment, or anything that may have blood on it. Do not donate blood, organs, tissue, or semen. Household and sexual contacts should be offered testing and advice about hepatitis B vaccination.

Seek urgent medical help for confusion, unusual drowsiness, fainting, repeated vomiting, vomiting blood, black stools, new bleeding or easy bruising, a rapidly swelling abdomen, severe abdominal pain, or difficulty staying hydrated. These can signal serious liver dysfunction or another complication that needs prompt assessment.

Contact your treating clinician promptly if yellowing deepens, urine becomes much darker, symptoms worsen instead of easing, or you cannot eat and drink normally. If you are pregnant, immunosuppressed, or already have liver disease, arrange early clinical guidance because monitoring and treatment decisions may differ.

Ask which blood results confirm an acute infection, what your liver tests show, when repeat testing is due, and which medicines or supplements to avoid. You can also ask how your close contacts should be tested and vaccinated, how long to follow transmission precautions, and what result would show that the virus has cleared.