why should medicines prepared as suspension be shaken well before use

Medicines prepared as suspensions should be shaken well before use to ensure that the active drug particles, which may have settled at the bottom, are evenly redistributed throughout the liquid. This uniform dispersion is crucial to provide a consistent and accurate dose of the medication with each use. Without shaking, the concentration of the drug in the dosage could be uneven, leading to potential under-dosing or overdosing, which can affect the medication's effectiveness and safety, especially for drugs with a narrow therapeutic index.