EEG changes following use of cyclopentolate 1% eye drops
Reviewed by Fiona Rowe

Cycloplegic eye drops may affect the central nervous system. This study reports electroencephalogram (EEG) changes in a cohort of 6–15-year-old children. EEG recordings were taken after placebo and two doses of cyclopentolate 1% in 24 awake children (36 children had been recruited but 12 fell asleep during recordings so were excluded). The main finding during eyes-closed recordings was a significant decrease of central, frontal, occipital and parietal Beta-1-power; central, frontal, occipital and Alpha-2-power; and occipital activation synchrony index. Main findings during awake eyes-open were a significant increase of temporal Beta-1, -2 and -3-power, and frontal and central and frontal Theta / Beta ration; and significant decrease in parietal and occipital Alpha-2-power, frontal Delta-1-power, frontal total power and occipital and parietal activation synchrony index. Nine children reported adverse reactions including impaired memory and impaired alertness. This was a pilot study but confirmed significant altered EEG parameters. Altered consciousness, drowsiness and sleep are indications that cyclopentolate has the potency to act as a short-acting central nervous system depressant. Regardless, the authors report it can be safely used in ophthalmic practice.

EEG changes as an indication of central nervous system involvement following cyclopentolate 1% eye drops; a randomised placebo-controlled pilot study in a pediatric population.
Van Minderhout HM, Joosse MV, Klaasen ES, Schalij-Delfos NE.
STRABISMUS
2023;31(2):82–96.