My last employer introduced the No Time Off For Appointments.
This meant I stopped receiving the medication I needed to keep me functioning - it was conditional upon attending hospital regularly for blood tests (that couldn't be done at the GP) and reviews of my blood results (so I wouldn't die).
Took about 9 months of pain and misery before it got so bad that I lied about why I wasn't coming into work, as apparently, a migraine was acceptable (possibly because the boss suffered from them), went to the GP and, whilst frantically trying to get me seen by a specialist, issued me with a sick note. I was off for three months and was then off every Friday for six more with various treatments, tests and procedures. Cost them a fortune, as in sending me to Occy Health to 'establish if what she is claiming is true' - yep, the OH Professional was so enraged by that, they showed me the referral form - OH subsequently reported back that not only had I fully disclosed everything prior to taking up employment and they'd cleared me, I now needed x adjustments as a direct result of their refusal to allow rests, suitable footwear, time off for appointments, etc, all of which were very expensive.
My union rep had a Field Day at the subsequent meeting when he pointed out that there was a very good case for direct disability discrimination and unless they'd rather pay the five figure compensation now and never hear from me again, he'd happily see them in court. Or they could make the adjustments and never stop me from attending essential appointments again/penalise me financially for doing so.
I have to admit that I was slightly disappointed that they apologised (after being given instructions from the board to do so) and made the adjustments. The cash would have been far more pleasant, as it was still bloody awful trying to drag myself through the week whilst hoping I'd go into remission soon.
Anyhow, you would be directly discriminating against somebody by penalising her financially for taking time off for NHS appointments for her condition. She isn't just popping to the GP and then going shopping for the rest of the day. She's hanging around bloody hospitals for half the day, if not longer - on one particular instance, I was waiting for my 9.10am appointment, didn't get seen until 11.17am, then had to go and wait for 3 x-rays, one ultrasound and a blood test. Each wait was an hour long with insufficient and inadequate seating. After which, I had a rather unpleasant procedure (45 minute wait). And then there was the trip back on public in rush hour when I couldn't walk properly.
I got home later than when I work a full day and spent the entire weekend in bed.
Strangely, even if you take into account my absences directly related to my disability/condition, I have a better sickness record than 92% of the staff - now I don't get penalised for needing it.