What is the recommended interval between multiple eye drops administered to the same eye?

• A. At least 5 minutes between drops
• B. 30 seconds between drops
• C. 10 minutes between drops
• D. No waiting required

Answer: (A)

When you apply more than one eye drop to the same eye, you want each medication a chance to contact the ocular surface and be absorbed without being washed away by the next drop. Waiting at least five minutes between drops lets the first drop spread, coat the eye, and start to work before the next drop is added, which improves effectiveness and reduces dilution or flushing of the first medication. A 30-second gap is usually too short to protect the first drop from being washed away, while waiting ten minutes is longer than typically needed for most regimens. No waiting at all would heighten the chance that the second drop washes out the first and lowers therapeutic benefit.