I know that some unis don't give you the jab any more, but some do when you enter the course. I just went to GP and said I need the Hepatitis B course because I haven't had it and need it for medical school. The practice nurse just did it all, first a blood test, two weeks later the first jab. And five months later the next jab. That is due end of November for me; and all for free! What kind of Doctors doesn't give you free injections?! I get loads from my GP and they have never mentioned any sort of charge. You could say you work in a hospital (I do), or find a country where it's required and say you are going there. But they really shouldn't ask, it's not your doctor's/nurse's business to know why you want the HEP B injection, just to give you it.