Tetanus

(Lockjaw)

Reviewed/Revised Jul 2023
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What is tetanus?

Tetanus is a life-threatening illness caused by a bacteria called Clostridium tetani.

  • The tetanus bacteria produce a poison that affects your nerves and brain

  • Tetanus can happen after a cut, puncture wound, burn, or any injury that lets germs in through your skin

  • Symptoms usually begin with strong muscle spasms 5 to 10 days after injury

  • You may have trouble swallowing and breathing, which can be fatal

  • Getting a tetanus vaccine helps prevent tetanus

See a doctor right away if you think you might have tetanus or if you have a puncture wound, a deep cut, or an injury that's hard to clean well.

What causes tetanus?

The bacteria that cause tetanus live in dirt and animal droppings. They can get into your body when you have:

  • A cut or puncture wound, especially one that is deep or has dirt in it

  • A puncture from a dirty needle (such as a tattoo needle or a needle you use to inject street drugs)

  • A skin injury such as a burn or frostbite

In parts of the world with poor sanitation, dirt can get into the umbilical cord stump and cause tetanus in newborns.

What are the symptoms of tetanus?

Symptoms start about 5 to 10 days after the injury, and sometimes as long as 50 days later. They include:

  • Muscle spasms that are painful and make your muscles tight and rigid

The muscle spasms usually start in your jaw. You can't open your jaw, which is why tetanus is sometimes called "lockjaw." The muscle spasms may affect your throat and breathing, and later your neck, shoulders, face, arms, legs, back, and belly. People with tetanus sometimes have their faces frozen in a smile with eyebrows raised. They may also have an arched back and trouble urinating (peeing) or passing stool (poop).

Other symptoms include:

  • Fast heartbeat

  • Fever and sweating

How can doctors tell if I have tetanus?

Doctors can tell if you have tetanus from your symptoms and by asking about any recent injuries you've had. They may take a sample of injured tissue to test for bacteria.

How do doctors treat tetanus?

People with tetanus are cared for in the hospital. Doctors will clean any cuts or wounds and remove dead skin tissue. Doctors will treat tetanus with:

  • Antibiotics into your vein through an IV

  • A shot of medicine to relieve muscle spasms

  • The tetanus vaccine, if you’ve never had it or haven’t had a booster shot in the last 10 years

  • Medicine for pain and anxiety

If you can’t breathe, doctors will insert a breathing tube into your throat and put you on a ventilator. If you can’t swallow, doctors will give you food and fluids into your vein through an IV.

How can I prevent tetanus?

You can prevent tetanus by getting the tetanus vaccine (shot). In young children, the tetanus vaccine is given along with vaccines for diphtheria and pertussis. Doctors give a series of 3 or more shots to young children. Adults should get a booster shot once every 10 years after that.

If you get cut or injured, be sure to clean the wound right away with soap and water. Then, call or visit your doctor to see if you need a tetanus shot. You'll need one if you haven’t ever had the tetanus shot or haven’t had a booster in the last 10 years.

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