I've no objection whatsoever to switching to generic versions of branded drugs. I don't care if the box my migraine tablets come in is labelled Imigran or sumatriptan, and any difference in efficacy is minimal.
I'm getting a bit pissed off with their efforts to change my hay fever (actually, multiple allergies and allergic rhinitis) meds for a cheaper one though. I've been prescribed acrivastine for about 20 years. Every now and then, a new one comes out and they get me to try it, that's fair enough. They never work as well as acrivastine, so I go back to it.
Lately, they've insisted on prescribing another anti-allergy "to try". Often, these are meds I've tried before and not stuck with them. They never work as well as acrivastine 3 x daily. Most of them seem to be one-a-day meds, which are especially shite, because my allergies are at their worst in the morning and evening, and whichever time of day I take them, they seem to lose their effectiveness within 24 hours.
About 20 years ago, I was referred to an immunologist who tried to get the the health authority (as it then was) to stump up £500 for a course of injections tailored for my specific allergens. These have a cumulative effect, and often desensitise patients to allergens for decades. They didn't want to know.
If I'd had the injections, I probably wouldn't need the bloody acrivastine and the savings would probably have covered the costs of the shots by now.
And then there's the sinus operation I might not have needed, had I not been permanently full of snot...