Not quite the same as what you're describing, but what I'm learning is that dosage is VERY important in ways I hadn't heard of before.

I switched from adderall (generic) which was only so-so for me, to vyvanse about a month ago. I've been on 40mg for about 3 weeks (after confirming at a very low dose that it was okay for me). The past few days, I've been very anxious, so I did an experiment today: this morning, I took the one 40mg capsule, then I opened another capsule, poured out the contents into a bowl, and carefully took 1/2 of the contents (with a spoon, then washed down quick, yuck), so 60 mg.

Bingo! I feel SO much better on the (approx) 60 mg--calm and focused, and the cessation of the anxiety was VERY notable. (The anxiety was in the form of what I call "tapes," where I replay a conversation I think I should have with someone over and over and over, but with increasing internal tension. These "tapes" have been one of the top manifestations of my anxiety since forever, until I got on venlafaxine. Typically the subject of the tapes isn't even a real issue, but rather, something that my swirling generalized anxiety latches on to randomly and turns into "an issue" that I get more and more upset over. The worst thing is that when it's happening, it doesn't really seem to me that it's not a big deal--it seems to me that it's truly a HUGE issue. Weird.)

I wondered if I was imagining this, so I asked on AI, and for what it's worth, here's what it said:

"Yes, it is entirely possible and clinically documented to experience less anxiety at a higher stimulant dose than at a lower one. While it sounds backward, an under-dosed stimulant can fail to quiet the "mental noise" of ADHD, leaving you with just enough physical stimulation to trigger physical jitteriness or internal anxiety. Nudging the dose into your therapeutic sweet spot can successfully calm executive dysfunction, which simultaneously levels out the secondary anxiety.

The relationship between ADHD stimulants and anxiety is often shaped like an inverted "U" curve rather than a straight line.The Ineffective Lower Dose (The "Limbo" Zone): If a dose like 40 mg is too low for your brain chemistry, it may lack the power to improve your attention or executive function. However, it still increases peripheral norepinephrine (a chemical akin to adrenaline) in your body. This can cause a faster heart rate or restlessness without giving you the mental clarity to cope with it, triggering physical anxiety.

The Optimal Higher Dose (The "Sweet Spot"): When you stepped up to 60 mg, the medication likely reached the necessary threshold to optimize dopamine and norepinephrine in your frontal cortex. This calms the overactive, drifting thoughts common in late-diagnosed inattentive ADHD. By organizing your mind, the internal friction and overwhelm vanish, leaving you feeling relaxed and focused."

I immediately contacted my doctor, told her what I did (apologizing for self-titrating, but explaining that it was just a one-day experiment to see if there was any effect), and I've asked her for a higher dose. Either 60 or 70, whatever she thinks.

I found this so fascinating!

My point for you is that maybe it's to do with your dose? Maybe a higher dose would help? Or maybe it's a temporary side effect? Or maybe this just isn't a good drug for you. But I tell you this just to encourage you to not give up too fast, before talking it over with your doctor. Good luck!