Sepsis

Learn more about the symptoms and treatment of sepsis, a serious infection-related illness.

Update Date: 02.10.2026

Overview
Symptoms
When to see a doctor
Causes
Risk factors
Complications
Diagnosis
Blood tests
Other lab tests
Imaging tests
Treatment
Medicines
Supportive care
Surgery

By Mayo Clinic Staff

Overview

Sepsis is a serious condition in which the body responds improperly to an infection. The infection-fighting processes overreact and cause inflammation throughout the body. As a result, the organs stop working as well as they're supposed to.

Sepsis may get worse and turn into septic shock. Septic shock is a dangerous drop in blood pressure that can damage the lungs, kidneys, liver and other organs. When the damage is severe, it can lead to death.

Early treatment of sepsis raises chances for survival.

Symptoms

Sepsis starts from an infection in one area that spreads to the rest of the body. The first symptoms are specific to the original infection. That may be pain when urinating if you have a urinary tract infection. Or it could be a cough that gets worse if you have pneumonia.

Once the infection spreads and becomes sepsis, symptoms include:

  • Change in mental status, such as feeling more confused or less alert than usual.
  • Fast, shallow breathing.
  • Sweating for no clear reason.
  • Feeling lightheaded.
  • Shivering.

Symptoms of sepsis can vary from person to person, and sepsis may look different in children versus adults.

Sepsis may get worse and turn into septic shock. Septic shock is a dangerous drop in blood pressure. It raises the risk of death. Symptoms of septic shock include:

  • Not being able to stand up.
  • Feeling very sleepy or having a hard time staying awake.
  • Major change in mental status, such as extreme confusion.

When to see a doctor

Any infection could lead to sepsis. See a healthcare professional if you have symptoms of sepsis or have an infection or wound that isn't getting better.

Symptoms such as confusion or fast breathing need emergency care.

Causes

Any type of infection can lead to sepsis. This includes bacterial, viral or fungal infections. Those that more often cause sepsis include infections of the:

  • Lungs, such as pneumonia.
  • Kidney, bladder and other parts of the urinary system.
  • Digestive system.
  • Bloodstream.

Other infections that more often cause sepsis are from catheter sites and wounds or burns.

Risk factors

Factors that raise the risk that an infection will turn into sepsis include:

  • Age, particularly being over age 65. Infants also are at higher risk.
  • Suppressed immune system, such as from taking medicines that lower your immune response. Having diabetes and other diseases also can weaken the body's defense against bacteria that cause infection.
  • Chronic disease, such as diabetes, kidney disease or chronic obstructive pulmonary disease (COPD).
  • Being admitted to an intensive care unit or staying in a hospital for a long time.
  • Having devices that go in the body, such as IV catheters that go in a vein or a breathing tube.
  • Antibiotic treatment in the last 90 days.
  • Corticosteroid treatment, which can lower immune response.

Taking steps to avoid infection can lower the risk. These include getting recommended vaccines for serious illnesses such as shingles or flu. These infections may be triggers for sepsis.

Complications

As sepsis worsens, the brain, heart, kidneys and other vital organs don't get as much blood as they should. Sepsis may cause blood-clotting issues. Small clots or burst blood vessels may occur and damage or destroy tissues.

Most people recover from mild sepsis, but septic shock can be deadly. Also, an episode of severe sepsis raises the risk of future infections.

Diagnosis

To diagnose sepsis, your healthcare team may order many tests to try to pinpoint the underlying infection.

Blood tests

Blood samples are used to test for:

  • Evidence of infection.
  • Changes in blood clotting.
  • Issues with liver or kidney function.
  • Lower levels of oxygen than the body needs.
  • Electrolyte imbalances.

Other lab tests

Other lab tests to find the source of the infection might include samples of:

  • Urine.
  • Liquid from the wound.
  • Saliva and mucus from the respiratory tract.

Imaging tests

If the site of the original infection is not known, a healthcare professional may order imaging tests. These might include:

  • X-ray. X-rays can show infections in the lungs.
  • Ultrasound. An ultrasound test uses sound waves to create real-time images on a video screen. Ultrasound can show infections in the gallbladder and kidneys.
  • Computerized tomography (CT). A CT scan takes X-rays from many angles and combines them to show cross-sectional slices of the inside of the body. Infections in the liver, pancreas or other abdominal organs are easier to see on CT scans.
  • Magnetic resonance imaging (MRI). MRI uses radio waves and a strong magnet to produce cross-sectional or 3D images. It can help show soft tissue or bone infections.

Treatment

Early, thorough treatment raises the chances of recovery. People who have sepsis need close monitoring and treatment in a hospital. This is because people with sepsis may need lifesaving measures to help them breathe and keep the heart working.

Medicines

Different medicines are used in treating sepsis and septic shock. They include:

  • Antibiotics. Treatment with antibiotics begins as soon as possible. Broad-spectrum antibiotics, which are effective against a variety of bacteria, are often used first. When blood test results show which type of bacteria is causing the infection, the first antibiotic may get switched out for a second one. This second one targets the germ causing the infection.
  • Fluids added to veins. The use of IV fluids begins as soon as possible.
  • Vasopressors. Vasopressors narrow blood vessels and help raise blood pressure. A vasopressor medicine may be used if blood pressure is too low even after receiving fluids.

Other medicines may be used, such as insulin for blood sugar levels or painkillers.

Supportive care

People who have sepsis often get supportive care that includes oxygen. Some people may need a machine to help them breathe. If the kidneys aren't working well because of the infection, dialysis may be needed.

Surgery

Surgery may help to remove sources of infection. Sources may include pus, infected tissues or dead tissues.

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