The Endocrine Society Clinical Practice Guidelines on congenital adrenal hyperplasia (CAH) recommend against using hydrocortisone suspension based on a study that examined a commercial suspension. Our objective was to examine the absorption of an extemporaneously prepared hydrocortisone suspension and compare it to tablets. Secondary objectives were to evaluate the 17-hydroxyprogesterone and androstenedione adrenal steroid responses. Using a parallel design, 34 children diagnosed with CAH received either suspension (n = 9; median age 1.8 years) or tablets (n = 25; median age 7.5 years). Patients were given their usual morning hydrocortisone formulation and dose; 12 serial blood samples were obtained and the area under the curve (AUC) was calculated. The mg/m2 dose-normalized cortisol AUCs were no different in the suspension and tablet groups (P = ·06), nor was there a significant difference in the Cmax or Tmax (P = .08 and P = .41, respectively). Although there were no differences in the 17-hydroxyprogesterone change-from-baseline AUCs, baseline concentrations, or the nadir concentrations when comparing suspension and tablet formulations, the androstenedione values were significantly lower as expected in the younger aged suspension group. Our results offer compelling evidence that an extemporaneously prepared hydrocortisone suspension provides comparable cortisol exposures to commercially available tablet formulations in children and can be used to safely and effectively treat CAH.