ADHD medication stopped feeling effective

I was diagnosed with ADHD and prescribed Inspiral 10 mg. The first 2–3 days were honestly amazing — I could start studying without fighting myself, barely touched my phone, felt calmer, had less daydreaming, and actually had motivation.

But now, even when I take it, I don't feel much of an effect. It also seems to last only a few hours. I haven't been taking it consistently, and I never actually took the second daily dose my doctor prescribed.

I'm going to discuss this with a new psychiatrist, but I'm curious about other people's experiences.

What medications/formulations should I ask my psychiatrist about if I want something that lasts longer? I'm NOT asking for a dose recommendation — just want to know what options people have discussed with their doctors and what worked for them.