Hi, Tdap vaccine contains diphtheria, tetanus and acellular pertussis which is a combination immunizing agent given by injection to protect against infections caused by diphtheria, tetanus and pertussis. The vaccine is to be administered only by or under the supervision of the doctor. Its side effects are pain, redness or swelling at the injection site, fever, agitation, back pain, bleeding gums, black or tarry stools, blood in the urine or stools, blurred vision, confusion, cough, bloody nose, dizziness, drowsiness, fast heartbeat, headache, irritability, joint pain, loss of bladder control, loss of consciousness, muscle pain, weakness, chest pain, unusual bruising, nausea, vomiting, abdominal pain, loss of appetite, fussiness, pinpoint red spots on the skin, allergic reactions etc. If you suffer from such type of side effects for long or bother you, you should consult your doctor promptly. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Zubayer Alam, General And Family Physician,