By blocking muscarinic receptors, cyclopentolate produces dilatation of the pupil (mydriasis) and prevents the eye from accommodating for near vision (cycloplegia). (en)
Oral LD<sub>50</sub> in the rat is 4000 mg/kg and 960 mg/kg in the mouse. Symptoms of overdose include tachycardia, dizziness, dry mouth, behavioral disturbances, uncoordination and drowsiness. (en)