This may be the reason that the prescribed dose is no longer always effect for you. Taking more than the prescribed dose can lead to a variety of other significant problems. I'm not aware of any studies linking Adderal to increases in viral load, however drug interactions with HIV medications are extremely common. Dose adjustments may be warranted for people on HIV drugs who require use of antidepressants and other psychotropic medications that are metabolized by a liver enzyme system called P450. Unfortunately specific drug interaction studies with each possible combination are lacking.
Close monitoring is necessary.
One drug interaction that is known involves adderal and lithium. Lithium often inhibits the stimulatory effects of amphetamines. First and foremost you should have your psychiatrist and your HIV specialist confer and discuss your therapy. You have two medical conditions, both of which require complex drug therapy. Your two specialists need to work together to optimize your medication regimen.