Hepatitis B often causes no symptoms at all. When it does, acute illness can bring fatigue, fever, poor appetite, nausea, belly pain, joint pain, dark urine, pale stools, and yellowing of the skin or eyes (jaundice). Symptoms usually appear about three months after exposure, but a blood test — not how you feel — is what confirms it.
treatable, not curable
testing, not symptoms, decides
| Item | Value |
|---|---|
| Curable? | managed — treatable, not curable |
| Tested by | exam + lab |
| Often | no symptoms |
| If you may have it | get tested — testing, not symptoms, decides |
What are the symptoms of hepatitis B?
Hepatitis B is a vaccine-preventable liver infection caused by the hepatitis B virus (HBV), spread mainly through blood and sex CDC. The first thing to understand is that most infections are quiet. Many people clear the virus, or carry it for years, without ever feeling sick. When the immune system does mount a response against infected liver cells, that inflammation is what produces the classic acute illness — and the symptoms reflect a liver that's struggling to do its job.
Here's what acute hepatitis B can feel like, and why each symptom happens:
- Fatigue — a deep, persistent tiredness that rest doesn't fix, often one of the earliest and most common signs as the liver becomes inflamed.
- Fever and joint pain — low-grade fever and achy joints come from the immune system reacting to the virus, sometimes before any liver symptoms show up.
- Loss of appetite and nausea — when the liver is inflamed, digestion and the handling of fats falter, which dulls appetite and can trigger nausea or vomiting.
- Abdominal pain — typically felt in the upper right side, where the liver sits, as the organ swells and its capsule stretches.
- Dark urine — urine the color of tea or cola happens when bilirubin, a yellow pigment the liver normally processes, spills into the blood and is filtered out by the kidneys.
- Clay-colored or pale stools — stool gets its brown color from bile; when the inflamed liver can't move bile into the gut, stools turn pale or gray.
- Jaundice — yellowing of the skin and the whites of the eyes, the most recognizable sign, caused by that same backed-up bilirubin. It's often the symptom that finally sends someone to a clinician.
The less obvious signs — and the silent cases
A lot of hepatitis B never announces itself. Children, especially infants, are far more likely to have no symptoms at all. Most people with chronic HBV — infection that lasts beyond six months — feel completely well for years even while the virus slowly damages the liver in the background. That's the dangerous part: the absence of symptoms doesn't mean the absence of disease.
The subtler clues are easy to dismiss. Itchy skin, vague joint aches, a run-down feeling you blame on stress, or urine that's a shade darker than usual can be the only hints. Because none of these are specific to the liver, they're routinely chalked up to something else — which is exactly how chronic infection goes undetected for decades.
How soon do symptoms appear after exposure?
Hepatitis B has a long incubation period. On average, symptoms start about 90 days after exposure, with a range of roughly 60 to 150 days CDC surveillance. That gap matters for two reasons. First, the timing makes it hard to connect the illness back to a specific encounter months earlier. Second, you can be infectious — and a blood test can turn positive — well before you feel anything, which is why testing on the right schedule beats waiting for symptoms. If you've had a possible exposure, see when to test after exposure to time it correctly.
What people mistake hepatitis B for
The early phase mimics a lot of ordinary illnesses. Fatigue, fever, nausea, and joint pain look like the flu or a stomach bug, so most people don't suspect their liver at all. By the time jaundice appears, some assume it's a gallbladder problem or a reaction to a medication or alcohol. Others confuse hepatitis B with hepatitis A or C — they overlap heavily and can't be told apart by symptoms alone.
This overlap is the whole point. These conditions share too many signs to separate by sight, and several are frequently silent. A test — not the symptom — is what settles which one (if any) it is. That's why you usually can't self-diagnose hepatitis B; a guess only becomes an answer once it's confirmed in the lab.
How is hepatitis B confirmed?
Diagnosis uses a triple blood panel: HBsAg (signals active infection), anti-HBs (signals immunity or recovery), and total anti-HBc (signals past or current infection) CDC. The combination tells a clinician whether you're currently infected, protected, or have been exposed in the past. The CDC now recommends every adult aged 18 and older be screened at least once in their lifetime, and that pregnant people be tested in each pregnancy CDC 2023. To learn how the panel works and where to go, get tested — the full process is covered on our testing page, and you can read more about recognizing hepatitis b symptoms across the rest of this guide.
Testing itself is straightforward and accessible. Depending on what's being checked, you might give a blood draw, a urine sample, a self-collected swab, or have a quick exam. It's free or low-cost at health departments, Planned Parenthood, and Title X clinics, and results usually come back within a few days.
Why your age at infection changes everything
With hepatitis B, when you catch it largely determines what happens next. Caught in adulthood, the infection clears on its own in the great majority of people and becomes chronic in under 5 percent. Caught in infancy, it becomes lifelong in about 90 percent of cases. A newborn's immune system can't fully fight off the virus, so it settles in for life — which is precisely why the birth-dose vaccine and prenatal screening carry so much weight.
That difference also shapes treatment. Acute hepatitis B in adults usually needs only supportive care — rest, fluids, and time — while the body resolves it. Chronic HBV has no cure, but FDA-approved antiviral medicines can suppress the virus and protect the liver, and that care is managed by a liver specialist over the long term CDC treatment guidelines.
When to see a clinician
Get evaluated promptly if you develop jaundice, dark urine, pale stools, or persistent right-upper-abdominal pain — those point to active liver inflammation that needs attention. Don't wait for symptoms if you've had a known or possible exposure, since the virus is detectable before you feel sick. And if you've never been screened as an adult or you're pregnant, ask for the panel even if you feel perfectly fine, because chronic infection is usually silent until the damage is done.