Tetanus, diphtheria, and pertussis are serious diseases caused by bacteria.

Tetanus (lockjaw) causes painful tightening of the muscles that can lead to "locking" of the jaw so the victim cannot open the mouth, swallow, or breathe. Tetanus can lead to death.

Diphtheria can lead to breathing problems, paralysis, heart failure, or death.

Pertussis (whooping cough) causes severe long-lasting episodes of cough that can interfere with eating, drinking, or breathing. Pertussis can lead to pneumonia, seizures, brain damage, and death.

Diphtheria and pertussis are spread from person to person. Tetanus enters the body through a cut or wound.

The tetanus, diphtheria, and acellular pertussis adult vaccine (also called Tdap) is used to help prevent these diseases in people who are 10 to 64 years old.

Like any vaccine, the Tdap vaccine may not provide protection from disease in every person.

You should not receive this vaccine if you've ever had:

• a life-threatening allergic reaction to a vaccine containing tetanus, diphtheria, or pertussis; or
• decreased consciousness, seizures, or coma within 7 days after receiving a pertussis vaccine.

If you have any of these other conditions, your vaccine may need to be postponed or not given at all:

• seizures;
• a weak immune system (caused by disease or by using certain medicine); or
• Guillain-Barré syndrome within 6 weeks after receiving a tetanus vaccine.

You can still receive a vaccine if you have a minor cold. In the case of a more severe illness with a fever or any type of infection, wait until you get better before receiving this vaccine.

If you are pregnant or breastfeeding, your doctor or vaccination provider should determine whether you need a Tdap vaccine.

If you are pregnant, your name may be listed on a pregnancy registry to track the effects of this vaccine on the baby.

This version of the vaccine (Adacel, Boostrix) should not be given to anyone under the age of 10. Another vaccine is available for use in children younger than 10 years old.

Use Tetanus, Diphtheria, Acellular Pertussis Vaccine (Tdap)(Intramuscular) exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Becoming infected with diphtheria, pertussis, or tetanus is much more dangerous to your health than receiving this vaccine. However, like any medicine, this vaccine can cause side effects but the risk of serious side effects is extremely low.

Call your doctor at once if you have:

• severe pain, itching, swelling, or redness where the shot was given;
• high fever (over 102 degrees F);
• a light-headed feeling, like you might pass out;
• severe joint pain; or
• nervous system problems--numbness, pain, tingling, weakness, burning or prickly feeling, vision or hearing problems, trouble breathing.

Common side effects may include:

• nausea, vomiting, diarrhea, and/or abdominal pain;
• pain, redness, or swelling where the shot was given;
• headache or tiredness;
• body aches; or
• fever.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report vaccine side effects to the US Department of Health and Human Services at 1-800-822-7967.

Follow your vaccination provider's instructions about any restrictions on food, beverages, or activity.