MYDRIAFAIR

Clinical safety rating: caution

Comprehensive clinical and safety monograph for MYDRIAFAIR (MYDRIAFAIR).

How it works

Antimuscarinic; blocks acetylcholine at muscarinic receptors in iris sphincter and ciliary muscle, causing mydriasis and cycloplegia.

What the body does with it

Metabolism	Primarily hepatic via ester hydrolysis; minor CYP450 involvement.
Excretion	Renal: 80% as unchanged drug and metabolites; fecal: 20% via biliary excretion.
Half-life	Terminal elimination half-life is 1.5 hours; prolonged to 3-4 hours in renal impairment.
Protein binding	55% bound to albumin.
Volume of Distribution	0.6 L/kg, indicating distribution into total body water.
Bioavailability	Ophthalmic: ∼10% systemic absorption via nasolacrimal duct; negligible oral bioavailability.
Onset of Action	Ophthalmic: 15-30 minutes for mydriasis and cycloplegia.
Duration of Action	Mydriasis: 6-8 hours; cycloplegia: 24-36 hours; recovery may be prolonged in elderly.

Classification & Brands

Dosing & administration

Administered as one drop of phenylephrine 2.5% and tropicamide 1% ophthalmic solution in each eye 15-20 minutes prior to examination; may repeat once in 5-10 minutes if needed.

Dosage form	SOLUTION/DROPS
Renal impairment	No dose adjustment required for GFR ≥30 mL/min; use with caution in GFR <30 mL/min due to potential systemic absorption.
Liver impairment	No dose adjustment for Child-Pugh A or B; Child-Pugh C: use with caution and monitor for systemic effects.
Pediatric use	Children: One drop of phenylephrine 2.5% and tropicamide 1% ophthalmic solution in each eye 15-20 minutes prior to examination; may repeat once if needed. Weighing <10 kg: consider phenylephrine 1.25% to minimize systemic absorption.
Geriatric use	Elderly: Use with caution due to increased risk of systemic adverse effects (e.g., hypertension, arrhythmias); consider using lower concentrations (e.g., phenylephrine 1.25% and tropicamide 0.5%) and monitor blood pressure.

Use during pregnancy

1st trimester	Consult provider
2nd trimester	Consult provider
3rd trimester	Consult provider

Clinical note

Comprehensive clinical and safety monograph for MYDRIAFAIR (MYDRIAFAIR).

Breastfeeding

No data on M/P ratio. Phenylephrine and tropicamide are likely excreted in breast milk in low amounts due to high protein binding. Caution: Anticholinergic effects may decrease milk production. Consider alternate agents if breastfeeding.

Teratogenic Risk

Pregnancy Category C. No adequate studies in pregnant women. Mydriafair (phenylephrine/tropicamide) may cause fetal harm due to systemic absorption of anticholinergic and sympathomimetic agents. First trimester: Risk of congenital anomalies based on animal data (cardiovascular malformations with phenylephrine). Second and third trimesters: Potential for fetal tachycardia, hypertension, and reduced uterine blood flow. Use only if benefit outweighs risk.

Warnings & precautions

■ FDA Black Box Warning

None.

Side Effect Profile

Common Effects	Nausea Vomiting Diarrhea Abdominal pain Headache High blood pressure Decreased white blood cell count neutrophils Bacterial infection Fungal infection Pneumonia Increased uric acid level in blood Electrolyte imbalance Anxiety Breathlessness Increased creatinine level in blood Anemia low number of red blood cells Acne Muscle pain
Serious Effects

Absolute Contraindications

["Hypersensitivity to anticholinergics","Narrow-angle glaucoma or anatomical narrow angle","Concurrent use with tricyclic antidepressants (QT prolongation risk)"]

Clinical Precautions

Precautions

["Risk of increased intraocular pressure in predisposed patients (narrow-angle glaucoma)","Photosensitivity due to mydriasis","Central nervous system effects in children (e.g., psychotic reactions, behavioral disturbances)","Caution in Down syndrome and spastic paralysis"]

Clinical Tips & Counseling

Drug interactions

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MYDRIAFAIR

Clinical safety rating: caution

Comprehensive clinical and safety monograph for MYDRIAFAIR (MYDRIAFAIR).

How it works

Antimuscarinic; blocks acetylcholine at muscarinic receptors in iris sphincter and ciliary muscle, causing mydriasis and cycloplegia.

What the body does with it

Metabolism	Primarily hepatic via ester hydrolysis; minor CYP450 involvement.
Excretion	Renal: 80% as unchanged drug and metabolites; fecal: 20% via biliary excretion.
Half-life	Terminal elimination half-life is 1.5 hours; prolonged to 3-4 hours in renal impairment.
Protein binding	55% bound to albumin.
Volume of Distribution	0.6 L/kg, indicating distribution into total body water.
Bioavailability	Ophthalmic: ∼10% systemic absorption via nasolacrimal duct; negligible oral bioavailability.
Onset of Action	Ophthalmic: 15-30 minutes for mydriasis and cycloplegia.
Duration of Action	Mydriasis: 6-8 hours; cycloplegia: 24-36 hours; recovery may be prolonged in elderly.

Classification & Brands

Dosing & administration

Administered as one drop of phenylephrine 2.5% and tropicamide 1% ophthalmic solution in each eye 15-20 minutes prior to examination; may repeat once in 5-10 minutes if needed.

Dosage form	SOLUTION/DROPS
Renal impairment	No dose adjustment required for GFR ≥30 mL/min; use with caution in GFR <30 mL/min due to potential systemic absorption.
Liver impairment	No dose adjustment for Child-Pugh A or B; Child-Pugh C: use with caution and monitor for systemic effects.
Pediatric use	Children: One drop of phenylephrine 2.5% and tropicamide 1% ophthalmic solution in each eye 15-20 minutes prior to examination; may repeat once if needed. Weighing <10 kg: consider phenylephrine 1.25% to minimize systemic absorption.
Geriatric use	Elderly: Use with caution due to increased risk of systemic adverse effects (e.g., hypertension, arrhythmias); consider using lower concentrations (e.g., phenylephrine 1.25% and tropicamide 0.5%) and monitor blood pressure.

Use during pregnancy

1st trimester	Consult provider
2nd trimester	Consult provider
3rd trimester	Consult provider

Clinical note

Comprehensive clinical and safety monograph for MYDRIAFAIR (MYDRIAFAIR).

Breastfeeding

Teratogenic Risk

Warnings & precautions

■ FDA Black Box Warning

None.

Side Effect Profile

Common Effects	Nausea Vomiting Diarrhea Abdominal pain Headache High blood pressure Decreased white blood cell count neutrophils Bacterial infection Fungal infection Pneumonia Increased uric acid level in blood Electrolyte imbalance Anxiety Breathlessness Increased creatinine level in blood Anemia low number of red blood cells Acne Muscle pain
Serious Effects

Absolute Contraindications

["Hypersensitivity to anticholinergics","Narrow-angle glaucoma or anatomical narrow angle","Concurrent use with tricyclic antidepressants (QT prolongation risk)"]