OBJECTIVE: To evaluate the impact of clomiphene citrate on vision. DESIGN: Observational study. SETTING: Patients were referred to the University of Ottawa Eye Institute ophthalmology clinic from the Department of Obstetrics and Gynaecology of the Ottawa Hospital-General Campus. PATIENT(S): Eight adult females taking clomiphene citrate and experiencing visual disturbances. INTERVENTION(S): Patients received a comprehensive visual evaluation twice: once during a washout period, and once during an active clomiphene citrate treatment. MAIN OUTCOME MEASURE(S): Ophthalmologic examination, color vision, visual acuity, contrast sensitivity, visual fields using standard automated perimetry, and foveal flicker sensitivity at high (32 Hz) and low (8 Hz) temporal frequencies. RESULT(S): We found no differences between the washout and clomiphene citrate conditions for color vision, visual acuity, contrast sensitivity, and visual fields. The only statistically significant difference was found for foveal flicker sensitivity at 32 Hz in the right eye, with a similar trend in the left eye and at 8 Hz in both eyes. CONCLUSION(S): The effect of clomiphene citrate on vision was minimal, and the visual disturbances were reversible in all patients. A bilateral reduction in flicker sensitivity was the only observed visual disturbance. Women who experience visual symptoms associated with clomiphene citrate should be monitored, but therapy can usually be maintained.