Usage
This ophthalmic solution is primarily prescribed for treating superficial bacterial eye infections, such as bacterial conjunctivitis (pink eye). It also alleviates associated symptoms like redness, swelling, itching, and burning.
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Pharmacological Classification: Sulphacetamide: Sulfonamide antibiotic; Boric Acid and Zinc Sulphate Monohydrate: Antiseptics; Phenylephrine: Decongestant (alpha-adrenergic agonist).
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Mechanism of Action: Sulphacetamide inhibits bacterial growth by interfering with folic acid synthesis. Boric acid and zinc sulphate provide antiseptic action. Zinc sulfate also acts as an astringent. Phenylephrine constricts blood vessels in the eye, reducing redness and swelling.
Alternate Names
- Sulfin Eye Drop
- Phenosulf Eye Drop
- Zinkar Drop
- Sulphacetamide/Zinc Sulfate/Boric Acid combination
- Ophthalmic triple antibiotic combination
How It Works
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Pharmacodynamics: Sulphacetamide exerts bacteriostatic action by competitively inhibiting dihydropteroate synthase, preventing bacterial folic acid synthesis and subsequent growth. Boric acid and zinc sulfate possess antiseptic and astringent properties, contributing to antibacterial activity. Phenylephrine, an alpha-adrenergic agonist, causes vasoconstriction, reducing eye redness and swelling.
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Pharmacokinetics: The combination is administered topically as eye drops. Absorption is minimal into systemic circulation. Primarily eliminated through lacrimal drainage and potentially some transconjunctival absorption. Sulphacetamide, if absorbed systemically, is metabolized in the liver and excreted renally. Phenylephrine is metabolized by monoamine oxidase in the tissues and liver. Boric acid is excreted mainly unchanged in the urine. Zinc sulfate likely follows the same pathway if absorbed systemically.
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Mode of Action (Cellular/Molecular): Sulphacetamide competitively inhibits the enzyme dihydropteroate synthase within the bacterial cell.
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Elimination Pathways: Primarily lacrimal drainage; if absorbed systemically, hepatic metabolism and renal excretion.
Dosage
Standard Dosage
Adults: Instill 1–2 drops into the affected eye(s) every 2–4 hours. Reduce frequency as infection improves.
Children: Dosage should be determined by a pediatrician, based on the child’s age and weight. Safety and efficacy in infants under two months have not been established.
Special Cases:
- Elderly Patients: Monitor for systemic side effects, especially with prolonged use.
- Patients with Renal Impairment: Use with caution. Monitor renal function.
- Patients with Hepatic Dysfunction: Use with caution. Monitor liver function.
- Patients with Comorbid Conditions: Evaluate potential drug interactions, particularly for those with hypertension or cardiovascular disease due to the phenylephrine component.
Clinical Use Cases
The dosage for clinical use cases like intubation, surgical procedures, mechanical ventilation, ICU, or emergency situations remains consistent with the standard adult recommendation. It is typically not indicated for these situations.
Dosage Adjustments
Dosage modifications may be necessary depending on the patient’s condition and response to therapy.
Side Effects
Common Side Effects
- Burning or stinging in the eye
- Transient blurred vision
- Eye irritation
- Itching
Rare but Serious Side Effects
- Severe allergic reactions (anaphylaxis)
- Stevens-Johnson syndrome
- Toxic epidermal necrolysis
Long-Term Effects
No specific long-term effects are typically associated with short-term ophthalmic use. Prolonged use can potentially lead to secondary infections or local adverse reactions.
Adverse Drug Reactions (ADR)
Severe allergic reactions require immediate discontinuation and medical attention.
Contraindications
- Hypersensitivity to sulfonamides
- Hypersensitivity to any component of the formulation
- Infants under two months of age (safety and efficacy not established)
Drug Interactions
- Silver preparations (e.g., silver nitrate): Avoid concomitant use.
- Other ophthalmic medications: Consult a physician before using concurrently.
Pregnancy and Breastfeeding
- Pregnancy Safety Category: Consult a physician. Data regarding safety during pregnancy are limited.
- Breastfeeding: Consult a physician. Limited information is available regarding excretion in breast milk.
Drug Profile Summary
- Mechanism of Action: Sulfonamide antibiotic with antiseptic and decongestant components.
- Side Effects: Burning, stinging, blurred vision, irritation, itching. Rarely, severe allergic reactions.
- Contraindications: Sulfonamide hypersensitivity, infants under two months.
- Drug Interactions: Silver preparations, other ophthalmic medications.
- Pregnancy & Breastfeeding: Consult a physician.
- Dosage: Adults: 1-2 drops every 2-4 hours. Children: As directed by pediatrician.
- Monitoring Parameters: Observe for infection resolution and adverse reactions.
Popular Combinations
The sources do not provide information on popular combinations.
Precautions
- Assess for allergies and pre-existing eye conditions.
- Consult a physician regarding use during pregnancy and breastfeeding.
- Pediatric and geriatric patients should be monitored carefully.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Boric Acid + Phenylephrine + Sulphacetamide + Zinc Sulphate Monohydrate?
A: Adults: 1–2 drops in the affected eye(s) every 2–4 hours. Pediatric dosage: Consult a pediatrician.
Q2: What are the common side effects?
A: Burning or stinging, blurred vision, eye irritation, itching.
Q3: Can I use this if I am allergic to sulfa drugs?
A: No, this medication is contraindicated in patients with sulfonamide hypersensitivity.
Q4: Can pregnant or breastfeeding women use this medication?
A: Consult a physician before use during pregnancy or breastfeeding. Safety data are limited.
Q5: How long should I use these eye drops?
A: Continue until the infection resolves completely, as directed by the physician. Do not discontinue prematurely even if symptoms improve.
A: Remove contact lenses before instilling drops and wait at least 15 minutes before reinserting.
Q7: What should I do if I accidentally get this medication in my mouth or nose?
A: Rinse thoroughly with water.
Q8: What should I do if I experience severe eye pain or vision changes?
A: Discontinue use and seek immediate medical attention.
Q9: Can I use other eye drops at the same time?
A: Consult a physician before using other eye drops concurrently.
Q10: How should this medication be stored?
A: Store in a cool, dry place, away from direct sunlight and heat. Keep out of reach of children.
