Last reviewed 2026-04-20 · How we verify

Cyclogyl (CYCLOPENTOLATE)

Cyclogyl (Cyclopentolate) is a small molecule drug developed by Alcon Labs Inc, targeting the muscarinic acetylcholine receptor M3. It is a cyclopentolate drug class, approved by the FDA in 1974 for indications such as cycloplegia, dilated pupil, and perioperative mydriasis. Cyclogyl is off-patent, with 8 generic manufacturers available. As a muscarinic receptor antagonist, it works by blocking the action of acetylcholine, leading to pupil dilation and paralysis of accommodation. Key safety considerations include potential systemic effects and interactions with other medications.

At a glance

Approved indications

• Cycloplegia
• Dilated pupil
• Perioperative Mydriasis

Common side effects

• Seizures
• Coma
• Medullary paralysis
• Death
• Hallucinations
• Hyperactivity
• Disorientation as to time and place
• Failure to recognize people
• Ataxia
• Incoherent speech
• Restlessness
• Tachycardia

Key clinical trials

• Efficacy and Safety of Cyclopentolate Microdrops for Cycloplegic Refraction in Children (PHASE4)
• Adjusted Study Protocol: Within-Subject Paired-Eye Design Comparing Pilocarpine 0.1%, Phentolamine 0.75%, and Combination Therapy for Cyclopentolate Reversal in Children (NA)
• Assessing Patient Comfort, Anxiety, and Satisfaction During CR Comparing Conventional Drops With ROC (NA)
• Evaluation of a Protocol of Pupil Dilation Before Laser-assisted Cataract Surgery
• Cycloplegic Refraction in Pediatric Patients With Esotropia (PHASE4)
• The Efficacy of Hyperemesis Gravidarum on Macular Thickness, Corneal Thickness and Intraocular Pressure in Pregnancy (NA)
• Prevalence of Refractive Errors in Primary School Children
• Mydriatic Drops After Combined Surgery (NA)

Primary sources

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