Fig 2. Chemical stability of HU oral liquids stored in amber oral plastic syringes (left) and amber plastic bottles (right).

Initial concentrations (mg/mL): mortar—original capsules, 93.0 ± 0.5; mortar—generic capsules, 96.2 ± 1.4; mortar—powder, 97.2 ± 0.4; mixer—powder, 100.9 ± 0.7; QuartetRx—original capsules, 91.3 ± 0.7; QuartetRx—generic capsules, 93.6 ± 0.8. ●, mixer; ■, mortar; ▲, QuartetRx; red, powder; blue, generic capsules; black, original capsules.