Tropicamide + Phenylephrine Hydrochloride
Generic Details
Generic Name
Tropicamide-Phenylephrine-Hydrochloride
Other Names
- Mydfrin-T
Drug Class
- Ophthalmic antihistamine and vasoconstrictor combination
Chemical Formula
C17H20N2O3 • C9H13NO2 • HCl
Molecular Weight
438.91 g/mol (tropicamide) + 203.76 g/mol (phenylephrine) + 241.69 g/mol (hydrochloride)
Mechanism of Action
- Tropicamide causes pupil dilation by blocking muscarinic receptors in the eye, while phenylephrine constricts blood vessels in the eye, reducing redness and swelling.
Indications
- Dilated eye examination
- Ocular inflammation
- Conjunctivitis
Common Dosage Forms
- Eye drops
Typical Dosage
- 1 to 2 drops in the affected eye(s) instilled 15 minutes before the procedure
Pediatric Dosage
- Dosage should be individualized based on age and weight
Geriatric Dosage
- Lower doses may be needed due to age-related changes in drug metabolism
Side Effects
- Burning or stinging sensation
- Blurred vision
- Increased intraocular pressure
- Headache
Contraindications
- Hypersensitivity to any component of the product
- Closed-angle glaucoma
Pregnancy Category
- C - Consult healthcare provider
Lactation Safety
- Use with caution, minimal amounts are excreted in breast milk
Drug Interactions
- May interact with monoamine oxidase inhibitors (MAOIs)
Overdose Symptoms
- Severe headache
- Increased heart rate
- Confusion
Antidote for Overdose
- Supportive care and symptom management
Storage Conditions
- Store at room temperature between 15-30°C (59-86°F)
Pharmacokinetics
- Absorption: Absorbed through the mucous membranes of the eye
- Distribution: Distribution into ocular tissues
- Metabolism: Metabolized in the liver
- Excretion: Excreted in the urine
Precautions
- Use with caution in patients with narrow-angle glaucoma
Warnings
- Do not touch the dropper tip to avoid contamination
- Remove contact lenses before using eye drops