First, see if you can find a doctor who believes in adrenal fatigue and do the cortisol saliva test. Alternative DR's, DO's, ND's are a good place to start. Prescription cortisol will help a lot.
If that doesn't work, try Adrenal Cortex 250 mg, 1-2 each in morning and 1-2 each at noon. It's important to take twice a day to keep the levels up through the afternoon
If that doesn't work enough, add Licorice root, 450 mg 1-2ea, 2 times per day. Licorice will help keep the cortisol that you do have, circulating longer.
I've been taking the Adrenal cortex for a few years, but adding Licorice root did make a positive difference. I didn't feel an "over abundance" of energy like a stimulant, but the afternoon "crash" doesn't happen and I can get a lot done.