[Skgqie1]

For me, I've been on dexamphetamine sulphate for about five years. I had to have my dose adjusted after about a year, because I experienced what you mentioned (decreased efficacy). Once the dose was increased, the effect became pretty stable though (I'm currently on 45mg a day). I wouldn't say it completely negates my ADHD, but it definitely makes things a lot more manageable.

[Jarwain]

What did your dose look like at the start? & how did it progress over the 5 years?

[Skgqie1]

I believe it was 30mg (10mg, 3x a day) that I started on. Dosage was adjusted after about a year, when I began to notice the dosage wasn't really having the same effect. Was upped to my current dose that I've been on since then.