Tropicamide

• Type: Mydriatic & Cycloplegic agent

• Main Use: Temporarily dilates the pupil (mydriasis) and relaxes the eye’s focusing muscle (cycloplegia) for eye examinations or certain treatments.

How It Works

• Tropicamide blocks muscarinic receptors in the eye (parasympathetic pathway).

• This causes the iris sphincter muscle to relax → pupil enlarges.

• Also relaxes the ciliary muscle → stops accommodation (focusing ability).

• These effects make it easier for doctors to examine the retina and other internal eye structures.

Common Uses

• Fundus examination (viewing retina and optic nerve during eye check-up)

• Refraction tests (to check for glasses power in children, as it stops accommodation)

• Pre-operative use before eye surgery (to keep pupil dilated)

• Sometimes used in uveitis to prevent painful muscle spasms in the eye and stop synechiae (adhesions inside the eye)

Advantages

• Works quickly (pupil dilation usually starts in 15–30 minutes)

• Short duration of action (effects usually wear off in 4–6 hours)

• Well tolerated compared to longer-acting agents like atropine

Possible Side Effects

• Temporary blurred vision (because the pupil stays wide open)

• Sensitivity to bright light (photophobia)

• Mild stinging after instillation

• Rarely, increased eye pressure (important in glaucoma patients)

• Systemic effects (very rare): dry mouth, rapid heartbeat, headache

Precautions

• Not recommended in patients with angle-closure glaucoma unless under strict supervision, as dilation may trigger an attack.

• Wear sunglasses until the effect wears off to reduce light sensitivity.

• Avoid driving until vision returns to normal.

• Use with caution in infants and elderly, as they may be more sensitive to systemic effects.