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.

Becoming infected with tetanus, diphtheria, or pertussis is much more dangerous to your health than receiving this vaccine.

This vaccine is given as an injection (shot) into a muscle.

Tdap vaccine is usually given as a one-time injection. Unless your doctor's tells you otherwise, you will not need a booster vaccine.

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.

Since the Tdap vaccine is usually given only once, you are not likely to miss a dose.

An overdose of this vaccine is unlikely to occur.

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

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.

Tetanus, diphtheria, acellular pertussis vaccine may cause serious side effects. 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 of tetanus, diphtheria, acellular pertussis vaccine 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.

Before receiving this vaccine, tell your vaccination provider about all other vaccines you have recently received.

Also, tell the vaccination provider if you have recently received drugs or treatments that can weaken the immune system, including:

• steroid medicine;

• cancer treatments;

• medicine to treat psoriasis, rheumatoid arthritis, or other autoimmune disorders; or

• medicines to treat or prevent organ transplant rejection.

If you are using any of these medications, you may not be able to receive the vaccine, or may need to wait until the other treatments are finished.

This list is not complete. Other drugs may affect this vaccine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.