What is the cap color used to identify alpha-agonists on packaging?

• A. Teal
• B. Baby blue/yellow
• C. White
• D. Purple

Answer: (D)

Color coding on glaucoma eye drop packaging is a quick cue for drug class, helping clinicians and patients avoid mix-ups. Purple caps are used to identify alpha-adrenergic agonists, such as brimonidine and apraclonidine, on packaging. This visual cue distinguishes them from other glaucoma drug classes, which use different cap colors, aiding safe selection and dispensing. The alpha-agonists work by reducing aqueous humor production and can cause systemic effects like dizziness or hypotension, so recognizing this class at a glance supports appropriate use and monitoring. While color conventions can vary by brand and region, purple is commonly used for alpha-agonists in many packaging designs.