I have a medical problem, you know the one and the last time I had an interview I was carrying around a machine as treatment but I took it off for the interview. With this treatment I would have had to go to the doctors 3 times a week and would probably be late for work 3 times a week, so not only was the possibility of them discriminating me to not let me have the job due to medical problems but I would be getting a job on false pretense's. I mean imagine hiring somebody and then find out they have to have days off for what could be a year or a few weeks or they can't work the hours they are contracted for.

At least in America, you'd be covered under Americans with Disabilities Act since the treatment of that... thing... is not a short-term deal. It'd be illegal for an employer not to hire you and he couldn't fire for you for it (or not hire you) unless it would cause undue hardship on him. Scheduling around your doctor's visits isn't too big of a deal. I'm fairly certain they aren't even allowed to ask if you have medical problems in the interview process. Britain might be different.

Then you'd get fired for showing up late all the time.

Really depends on the employer and the job, but most are willing to schedule around your visits as long as you can provide them long enough ahead of time. I'd rather work my schedule around a good worker than have to hire a comparatively shitty one. It might not even be a problem. If your doctor's appointments are normally in the mornings, find a job that works evenings/graveyard shifts, etc.