Most STIs don't cause nausea and vomiting. The exception is viral hepatitis, hepatitis A, B, and C, which inflame the liver and commonly bring nausea, loss of appetite, and vomiting, often with fatigue, jaundice, and dark urine. HIV's early flu-like phase can also include nausea. A blood test confirms which one.
Key figures
- Hepatitis A
- self-limiting
- Hepatitis A virus
- Hepatitis B
- managed
- Hepatitis B virus
- Hepatitis C
- curable
- Hepatitis C virus
- HIV
- managed
- Human immunodeficiency virus
| Item | Value |
|---|---|
| Hepatitis A | self-limiting: Hepatitis A virus |
| Hepatitis B | managed: Hepatitis B virus |
| Hepatitis C | curable: Hepatitis C virus |
| HIV | managed: Human immunodeficiency virus |
Quick answer: which STIs can cause nausea and vomiting?
When nausea and vomiting trace back to a sexually transmitted infection, the liver is almost always involved. The short list is the three viral hepatitis infections, hepatitis A, hepatitis B, and hepatitis C, plus the early, flu-like phase of HIV. These viruses irritate the liver or trigger a systemic immune response, and the gut reacts with queasiness, a poor appetite, and sometimes vomiting. Bacterial STIs like chlamydia and gonorrhea don't typically do this unless they spread to the upper abdomen or pelvis.
Which STIs cause nausea and vomiting
Hepatitis A
Hepatitis A is a viral liver infection caused by the hepatitis A virus. It's the most likely to announce itself loudly: when an adult gets symptoms, nausea sits front and center alongside fatigue, abdominal pain, jaundice (yellowing of the skin or whites of the eyes from a buildup of bilirubin), dark urine, and pale, clay-colored stools CDC. Not everyone feels sick: adults are more likely to than children, and young kids are often infectious with no signs at all. When symptoms do appear, they usually surface two to seven weeks after exposure. Hepatitis A does not become chronic, and people recover completely. For a full breakdown of the timeline, see hepatitis A symptoms.
Hepatitis B
Hepatitis B is a vaccine-preventable liver infection caused by the hepatitis B virus, spread mainly through blood and sex CDC. Many people have no symptoms at all. When acute illness does occur, nausea and vomiting come bundled with fatigue, fever, poor appetite, abdominal pain, dark urine, clay-colored stools, joint pain, and jaundice. The timing is slower than hepatitis A: symptoms average about 90 days after exposure, with a range of roughly two to five months. Acute means the first six months. If the virus persists beyond that, it's chronic and can be lifelong, and most people with chronic infection feel nothing. Read more about hepatitis b symptoms.
Hepatitis C
Hepatitis C is a liver disease caused by the hepatitis C virus, spread when infected blood enters another person CDC. It's the quietest of the three, and most infections cause no symptoms at all. Jaundice shows up in only about 20–30% of cases, and nonspecific symptoms like fatigue, poor appetite, abdominal pain, and dark urine in roughly 10–20%. When symptoms do come, they appear an average of two to twelve weeks after exposure. Most people who catch it develop a chronic, lifelong infection that can stay silent for twenty years or more, which makes it dangerous. Unlike hepatitis B, hepatitis C is now curable, with treatment clearing the virus in more than 95% of people hepatitis c cure.
HIV
HIV is a virus that attacks the immune system CDC. Nausea isn't its hallmark, but the acute retroviral syndrome, the flu-like illness that hits two to four weeks after infection, can include nausea. The classic features are fever, chills, rash, night sweats, muscle aches, sore throat, fatigue, swollen lymph nodes, and mouth ulcers HHS. Plenty of people have no symptoms whatsoever, so testing is the only way to know. After this early phase, HIV often goes years without symptoms (clinical latency), so a brief queasy spell weeks after a risk shouldn't be dismissed. Starting treatment early protects your health and your partners, earlier HIV treatment.
When it's NOT an STI
Nausea and vomiting come from countless everyday causes that have nothing to do with sex. Stomach viruses ("the stomach flu"), food poisoning, migraines, pregnancy, motion sickness, medication side effects, anxiety, and ordinary indigestion all top the list and are far more common than hepatitis. What pushes hepatitis up the list is jaundice, yellow eyes or skin, or nausea plus dark urine and pale stools after a known exposure or risk. Without those liver-specific signs, a brief bout of nausea is much more likely to be something benign and self-limiting.
How to tell them apart
You usually can't tell them apart by feel. The hepatitis viruses share nearly identical symptoms, several are frequently silent, and the same nausea-and-fatigue picture overlaps with a dozen non-STI illnesses. Clinicians lean on timing (how long since a possible exposure), the presence of jaundice or dark urine, and your specific risk history. But these clues narrow the field rather than answer it. A test settles which infection, if any, you actually have.
Side-by-side comparison
| Infection | Becomes chronic? | Typical timing after exposure | Nausea/vomiting pattern | Other tell-tale signs |
|---|---|---|---|---|
| Hepatitis A | No, full recovery | 2–7 weeks | Common in symptomatic adults | Jaundice, dark urine, clay stools, fatigue |
| Hepatitis B | Sometimes (beyond 6 months) | ~90 days (range 60–150) | Common in acute illness; often none | Fever, joint pain, jaundice, dark urine |
| Hepatitis C | Usually, often lifelong | 2–12 weeks (range 2–26) | Uncommon; mostly silent | Jaundice in 20–30%, often no symptoms |
| HIV (acute) | Lifelong virus | 2–4 weeks | Possible, part of flu-like illness | Fever, rash, sore throat, swollen nodes |
How it's tested
All four are diagnosed with blood tests. Hepatitis A is confirmed with a blood test; hepatitis B uses a triple serologic panel (HBsAg for active infection, anti-HBs for immunity, and total anti-HBc for past or current infection) CDC, 2023; hepatitis C starts with an antibody test and reflexes to a NAT for HCV RNA if positive USPSTF; and HIV uses NAT, antigen/antibody, or antibody tests depending on how recent the exposure was CDC. In practice, testing is quick and undramatic, a urine sample, a self-collected swab, or a quick exam depending on what's suspected, and it's free or low-cost at health departments, Planned Parenthood, and Title X clinics, with results usually back in a few days. You can get tested when something feels off.
What to do next
If nausea follows a sexual risk, especially with jaundice, dark urine, or pale stools, get a hepatitis and HIV panel rather than guessing. Timing matters, because a test taken too early can miss a real infection. Check when to test after exposure so your result actually means something, then confirm a diagnosis before starting any treatment, since the right care differs completely between hepatitis A, B, C, and HIV.
Red flags, when to get seen urgently
- Yellowing of the eyes or skin (jaundice), a sign the liver is struggling and needs prompt evaluation.
- Persistent vomiting that keeps you from holding down fluids, which risks dehydration.
- Severe or worsening upper-right abdominal pain over the liver.
- Confusion, extreme drowsiness, or difficulty staying awake, possible signs of serious liver dysfunction.
- Dark, tea-colored urine together with pale, clay-colored stools.
- High fever with these symptoms after a recent exposure.
Keep exploring on EasySTD: STD vaccines, your risk of an STD and Hepatitis A testing.