Can I drive after those drops, doctor?

Purpose: To document the experience of patients driving after drops to dilate the pupils. There are no documented guidelines on driving after pupillary dilatation. This is a study of patients who drove a car after attending the eye casualty for an ocular examination during which their pupils were dilated.

Methods: Thirty patients were identified who felt confident to drive after their pupils were dilated. Distant visual acuities, colour vision and confrontation visual fields were assessed before and after pupillary dilatation with 2.5% phenylephrine and 1% tropicamide. These patients met the legal requirements for driving after pupillary dilatation. The patients completed a questionnaire that recorded their subjective experiences of driving while their pupils were dilated.

Results: The mean age of the patients was 51.9 +/- 19.7 years (range 20-73 years). Twenty-seven of the 30 patients undertook the journey on familiar roads, and 14 of 30 wore spectacles. The mean spherical equivalent was +2.00 dioptre sphere for distance and a mean additional spherical equivalent of 1.75 dioptre sphere for near. Twenty patients experienced glare, which was severe enough to cause difficulty driving in three cases. Two of these patients drove in sunny weather conditions and one in light (not sunny) weather. Six patients had difficulty with road signs, two had difficulty judging distances and one reported difficulty with traffic lights.

Conclusions: Dilating the pupils did not reduce distance visual acuity. However, it would seem appropriate to warn patients of the problems associated with glare and, if driving is their only option for transport home, recommend that they allow sufficient time to adapt to a dilated pupillary state, drive only on familiar roads and avoid driving in sunny weather.