The side effects of having the jab are usually minor and also minimised by the nurse or GP asking you health related questions before giving it. She / He will only give it if satisfied that you are well enough to have it. No medical procedure is totally free of risk, flu vaccines are generally very safe. The most common reaction to the jab is a sore arm, or you may feel hot for a day or two after the vaccination. This is easily treated by Paracetamol. It is not the flu but a reaction to the injection.
I am diabetic and definitely have the flu jab every year and have been free of flu since I have been having it.
Answered by: Dr. Azra Parvez, GP and GP Trainer - Parkside Medical Centre