Sick Notes
Your employer cannot ask you to provide an official sick note for the first 7 days that you are sick. They may ask you to fill in a self-certificate of their own or form SC2 which you can get from the surgery or website http://www.hmrc.gov.uk/forms/sc2.pdf
If your employer demands a sick note for the first 5 working days your doctor may provide a private sick note for which there is a charge. You will need a doctor's appointment to obtain this.
If you think you are going to be off for more than 7 days then make an appointment with your GP for a sick note. Since October 2010 Med 3 sick notes have been replaced by "fit notes". For details about fit notes go to - What are fit notes? - Health questions - NHS Choices
If you have attended hospital or had an operation, please ask the hospital doctor or ward sister to give you a note. They are obliged to issue notes while you remain under their care. If, for example, you have a broken leg they should issue a note until your next out-patient review.
If you forget to get a note from the hospital the GP may be able to issue a note without having to see you once he has received written confirmation from the hospital of your incapacity. If needed, please ask the receptionist to find out if this is possible.
Incapacity Benefit has now been replaced by Employment Support Allowance (ESA). A Med 4 is no longer required.
http://www.dwp.gov.uk
or enquire at your local job centre plus office
Jobcentre Plus: Directgov - Local Office Search