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Antimuscarinic cycloplegic / mydriatic (ophthalmic) Pregnancy: Use with caution; single-use ophthalmic application — systemic absorption minimal.

Cyclopentolate 1% Eye Drops (Mydrilate)

Brand names: Mydrilate, Minims Cyclopentolate

Adult dose

Dose: 1 drop of 1% solution; repeat after 15 minutes if needed
Route: Ophthalmic
Frequency: Single application; may repeat once after 15 minutes
Max: 2 drops per eye per examination
Cycloplegia for refraction: 1 drop 1%, repeat after 15 minutes; examine 30–45 minutes later. Mydriasis for fundal examination: 1 drop (onset 30–45 min; duration 6–24 hours). Anterior uveitis: 0.5–1% cyclopentolate to reduce ciliary spasm and prevent posterior synechiae. Warn patient about blurred vision and photophobia for 6–24 hours.

Paediatric dose

Route: Ophthalmic
Frequency: As per procedure
Max: 0.5% preferred in neonates and infants; 1% from age 3 months
Neonates: use 0.5% only (1 drop). Infants 1–3 months: 0.5% (1 drop). Children ≥3 months: 1% (1 drop, repeat after 15 min). Punctal occlusion essential to reduce systemic absorption. Systemic toxicity risk higher in children: tachycardia, fever, flushing, confusion, hallucinations.

Dose adjustments

Renal

No systemic dose adjustment for ophthalmic use.

Hepatic

No systemic dose adjustment for ophthalmic use.

Clinical pearls

  • Most commonly used cycloplegic in UK — faster onset and shorter duration than atropine
  • Cycloplegic refraction: examine child 30–45 minutes after instillation; results most accurate
  • Always warn patients (and parents): blurred vision 6–24 hours, do not drive until vision normal
  • Punctal occlusion in children is mandatory — reduces systemic absorption significantly
  • Atropine 1% used instead for highly hyperopic children requiring maximum cycloplegia (used for 3 days prior)

Contraindications

  • Narrow-angle glaucoma or shallow anterior chamber (risk of precipitating acute angle closure)
  • Hypersensitivity to cyclopentolate
  • Infants with Down syndrome (increased sensitivity)

Side effects

  • Blurred vision (near vision — cycloplegia)
  • Photophobia (mydriasis)
  • Raised IOP (in predisposed eyes)
  • Systemic anticholinergic effects (especially children): tachycardia, fever, flushing, dry mouth, urinary retention, hallucinations
  • Stinging on instillation

Interactions

  • Other antimuscarinics — additive systemic effects
  • CNS depressants — may enhance anticholinergic CNS effects in children

Monitoring

  • IOP pre and post if glaucoma risk
  • Pupil dilation response
  • Systemic vital signs in small children

Reference: BNFc; BNF; BNFc; RCOphth Refraction Guidelines; Mydrilate SPC. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

Pathways