[krono]

I share this experience myself, in particular the dosage not providing a consistent effect day to day - every specialist I've spoken has told me this is weird and shouldn't be happening and yet it is so. Switching to staged release medication (Medikinet CR) has helped me too.

Unfortunately extended release Methylphenidate of any kind/brand is only partially covered by Dutch health insurance[1], and I'm certain the cost is prohibitive for people who might be less well off.

1: In essence, the government has determined that all Methylphenidate variants are equal, and so you can just take the cheapest instant release variant or else pay the difference out of your own pocket.