Profound tabletability deterioration of microcrystalline cellulose by magnesium stearate

Magnesium stearate (MgSt) is a common lubricant used in tablet formulations to facilitate tablet manufacturing by reducing ejection force. The use of MgSt in tablet formulation is known to potentially deteriorate tabletability of plastic powders and slow down drug dissolution. Here, we report surprisingly profound deterioration in tabletability of microcrystalline cellulose by hand-mixing. We also show that the hand mixing process is highly variable. To ensure the reproducibility of tabletability assessment of powders, hand-mixing should be used with caution. For research that employs hand mixing, mixing procedure should be carefully controlled and reported.