What does "qs" refer to in the context of medication dosage?

In the context of medication dosage, "qs" stands for "quantity sufficient." This term is commonly used in pharmacy to indicate that the amount of a particular ingredient should be sufficient to achieve the desired effect or to fill the prescribed volume without specifying an exact measurement. For instance, when a prescription states "qs to 100 mL," it means that the pharmacist should add enough of the ingredient to ensure that the final volume of the preparation reaches 100 mL.

This terminology is particularly useful in formulations where precision in the amount of a specific component may not be as critical, allowing flexibility in the preparation process while still ensuring that the end product meets the required volume or dosage. Understanding this definition is important for pharmacy technicians, as it helps them accurately prepare medications and understand prescriptions given by healthcare providers.