In prescription shorthand, what does 'O.S.' signify?

The abbreviation 'O.S.' stands for "oculus sinister," which is Latin for "left eye." This notation is commonly used in prescriptions and medical records to specify which eye requires treatment or medication. Understanding this shorthand is essential for accurately administering medications, especially in scenarios involving eye care.

By recognizing 'O.S.' denotes the left eye, healthcare providers can ensure the correct eye is treated, which is critical for patient safety and effective care management. Knowledge of these abbreviations is vital for a Missouri Level 1 Medication Aide, as it directly relates to medication administration practices and ensuring proper communication among healthcare professionals.