Lemierre’s syndrome is a possibly life-threatening complication of an upper respiratory infection. The bacterium Fusobacterium necrophorum causes most cases. Without treatment, it can spread to other parts of your body and cause blood clots in your jugular vein and sepsis. Treatment includes antibiotics and, in severe cases, surgery.
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Lemierre’s (pronounced “la-MEERs”) syndrome is a potentially fatal complication that can develop from an infection in your upper respiratory tract — usually your throat. It can cause painful inflammation and infected blood clots (septic thrombophlebitis) in your jugular vein. These blood clots can spread to your:
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Lemierre’s syndrome is rare. There are fewer than 4 cases per 1 million people per year in the U.S. Most cases affect adolescents and young adults. But the number of cases has increased over the last several years. This may be because the medicines that usually treat Lemierre’s syndrome no longer kill the infection (antibiotic resistance).
The name comes from the French physician André Lemierre. He reported cases of the condition in the 1930s. Healthcare providers sometimes call it Lemierre disease.
The first symptom is usually a sore throat. But other Lemierre’s syndrome symptoms include:
The bacterium Fusobacterium necrophorum (F. necrophorum) causes over 8 out of 10 cases of Lemierre’s syndrome. People naturally carry F. necrophorum in their bodies. It appears in the:
Other bacteria that may cause Lemierre’s syndrome include:
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You’re at a greater risk of getting Lemierre’s syndrome if you’re an adolescent or young adult. Experts aren’t sure why.
Certain bacterial and viral infections may increase your chances of an F. necrophorum infection. These include:
These infections can damage the mucus membranes in your body. This may allow F. necrophorum to grow and spread more easily.
No, Lemierre’s syndrome isn’t contagious. But the bacteria and viruses that cause it can spread from person to person.
Lemierre’s syndrome complications may include:
Lemierre’s syndrome can also cause your immune system to overreact to an infection (sepsis). Sepsis is a life-threatening medical emergency.
Lemierre’s syndrome can be challenging to diagnose. That’s because it’s rare and shares many symptoms with other common infections. If your symptoms last for a long time or get worse, healthcare providers may first recommend blood tests that check for inflammation in your body. These include:
They may also perform a bacteria culture with some of your blood sample.
If blood tests indicate you may have an infection, providers may recommend imaging tests of your neck and throat. They can help identify blood clots in your jugular vein and other signs of infection or complications. These imaging tests may include:
The first-line treatment for Lemierre’s syndrome is antibiotics like:
In severe cases, you may need surgery to:
It depends on how severe your case is. It also depends on how you respond to treatment. Most people start to feel better a few days after starting antibiotics. But it may take three to six weeks to make a full recovery.
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Call a healthcare provider if you have a sore throat and other signs of a respiratory infection that don’t go away within a week or get worse. Go to the nearest emergency room immediately if you’re vomiting blood or having trouble breathing or swallowing.
You may want to ask a healthcare provider the following questions:
With a quick diagnosis and treatment, most people survive Lemierre’s syndrome and are less likely to develop complications. Without treatment, complications can be severe and even fatal. Healthcare providers will give you a better idea of what to expect.
You can help reduce your risk of getting infections that could lead to Lemierre’s syndrome by:
No, healthcare providers don’t consider Lemierre’s syndrome a sexually transmitted infection (STI). But the P. asaccharolytica is a rare cause of Lemierre’s syndrome. P. asaccharolytica doesn’t usually exist in your mouth or throat. It’s more common in your genitals and gastrointestinal (GI) tract. Healthcare providers believe the bacterium may spread from the genitals to the mouth after oral sex. Providers don’t consider Lemierre’s syndrome an STI because oral sex isn’t the main way that the infections that cause Lemierre’s syndrome spread.
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It’s possible to get Lemierre’s syndrome twice. But it’s very rare.
You might not hear a lot about Lemierre’s syndrome because it’s rare. But that doesn’t mean it’s not scary, especially because it commonly affects young, relatively healthy people. If you have a sore throat or other symptoms of an upper respiratory infection that won’t go away, get immediate medical attention. The sooner you get a proper diagnosis and treatment, the greater your chances of making a full recovery without any complications.
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Last reviewed on 08/15/2025.
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