Intestinal Permeability Study of Minoxidil: Assessment of Minoxidil as a High Permeability Reference Drug for Biopharmaceutics Classification

The study aimed to evaluate minoxidil as a high permeability reference drug for Biopharmaceutics Classification System (BCS). The results suggest that minoxidil may be an acceptable reference drug for BCS high permeability classification. Minoxidil exhibited constant membrane permeability across Caco-2 monolayers regardless of pH condition and direction, while metoprolol showed direction-dependent permeability and was pH-dependent. The study concluded that minoxidil can be used as a high permeability reference drug for biopharmaceutics classification.