Ritalin poop-out?

[msimm]

SWIM used to take high doses of Ritalin regularly. He definitely had a habit. Eventually he started to notice the pleasurable effect had diminished and the body load was becoming worrying. He stopped, which was probably the hardest thing he's stopped aside from cigarettes.

Anyway, 5 or 6 years later SWIM decided to try some again. For the clarity and euphoria he'd experienced before.

He purchased through a reputable source and received everything in unexpired/unopened blisters. However his experience 5 years down the road was the exact experience he'd had at the end of his previous use: high body-load, no clarity/euphoria. Felt kind of like having too many Redbull. Nothing like the experience he used to have.

What I'm curious about is if anyone else has had a similar reaction or if anyone knows why SWIM might have had this reaction. It's obvious that Ritalin is no longer a viable option for SWIM but it's puzzling him. Swim does have moderate ADD and works in a highly technical field. Were SWIM to attempt treatment he's worried he might be unable to benefit from related therapies altogether.

As a side note SWIM attempted low-dose, moderate dose, insufflation, with/without food and even (go ahead laugh, I should have) rectal administration. All with variations of the same results.

How does something that once worked so well suddenly stop working almost altogether?