Usage
- This combination medication is primarily used to treat superficial bacterial eye infections, such as conjunctivitis (pink eye) and blepharitis. It may also be used prophylactically after eye injuries or surgery to prevent bacterial infections.
- Pharmacological Classification: Antibiotic (Sulphacetamide), Antiseptic (Boric Acid and Zinc Sulphate)
- Mechanism of Action: Sulphacetamide is a sulfonamide antibiotic that inhibits bacterial growth by interfering with folic acid synthesis, a crucial step in bacterial DNA replication. Boric acid and zinc sulphate possess antiseptic properties, further contributing to bacterial growth inhibition and providing a soothing effect.
Alternate Names
- Sulphacetamide/Zinc Sulfate/Boric Acid combination
- Ophthalmic triple antibiotic combination
- Brand names: Several brand names exist for this combination, such as Opthosulf and Zinco Sulpha, among others (brand names vary regionally).
How It Works
- Pharmacodynamics: Sulphacetamide exerts its antibacterial effect by competitively inhibiting dihydropteroate synthase, a bacterial enzyme essential for folic acid synthesis. This inhibition disrupts the formation of purines and pyrimidines, necessary for DNA and RNA synthesis, leading to bacteriostatic action. Boric acid and zinc sulphate exert antiseptic effects, contributing to bacterial growth inhibition and providing a soothing effect on inflamed ocular tissues.
- Pharmacokinetics: Primarily administered topically as eye drops, systemic absorption is minimal. Limited information is available regarding its systemic metabolism and excretion due to the low systemic absorption after topical ocular administration. The primary mechanism of action occurs locally in the eye tissues.
- Mode of Action: Sulphacetamide acts by competitively inhibiting the bacterial enzyme dihydropteroate synthase.
- Receptor Binding, Enzyme Inhibition, or Neurotransmitter Modulation: Sulphacetamide acts through enzyme inhibition (dihydropteroate synthase).
- Elimination Pathways: Due to minimal systemic absorption, elimination pathways are not clinically relevant after topical ocular administration.
Dosage
Standard Dosage
Adults:
Instill 1-2 drops into the affected eye(s) every 2-4 hours initially. The frequency can be reduced as the infection improves, typically to 3-4 times daily.
Children:
Dosage should be determined by a pediatrician, considering the child’s age and weight. Generally, 1 drop in the affected eye(s) every 4-6 hours may be prescribed.
Special Cases:
- Elderly Patients: No specific dosage adjustments are typically necessary unless renal or hepatic impairment is present.
- Patients with Renal Impairment: Dosage adjustments might be required. Consultation with a nephrologist is recommended.
- Patients with Hepatic Dysfunction: Exercise caution; dosage adjustment may be needed. Consultation with a hepatologist is recommended.
- Patients with Comorbid Conditions: Evaluate for potential drug interactions or contraindications based on coexisting medical conditions.
Clinical Use Cases
- Clinical use cases for this specific drug combination are limited to the treatment of bacterial eye infections, such as conjunctivitis, and prophylaxis after eye injury or surgery. The sources do not provide dosage guidelines for intubation, surgical procedures, mechanical ventilation, ICU use, or emergency situations.
Dosage Adjustments
Dosage modifications should be based on individual patient responses and clinical judgment. Consider renal and hepatic function and other underlying medical conditions.
Side Effects
Common Side Effects
- Transient burning or stinging upon instillation
- Temporary blurred vision
- Eye irritation
- Itching
Rare but Serious Side Effects
- Severe allergic reactions (rash, hives, swelling, difficulty breathing)
- Stevens-Johnson syndrome
Long-Term Effects
No significant long-term adverse effects are typically associated with short-term use. Prolonged use can potentially alter the normal eye flora, increasing susceptibility to other infections.
Adverse Drug Reactions (ADR)
Severe allergic reactions require immediate discontinuation of the drug and appropriate medical management.
Contraindications
- Hypersensitivity to sulfonamides or any component of the formulation
- Known allergy to sulfa drugs
Drug Interactions
- Silver nitrate-containing ophthalmic preparations
- Polyvinyl alcohol-containing ophthalmic solutions
Pregnancy and Breastfeeding
Consult a doctor regarding use during pregnancy and breastfeeding. The safety profile during pregnancy and lactation is not well established.
Drug Profile Summary
- Mechanism of Action: Sulphacetamide inhibits bacterial folic acid synthesis; boric acid and zinc sulfate have antiseptic properties.
- Side Effects: Transient burning/stinging, blurred vision, irritation, itching (rarely: severe allergic reactions).
- Contraindications: Sulfonamide hypersensitivity.
- Drug Interactions: Silver nitrate, polyvinyl alcohol.
- Pregnancy & Breastfeeding: Consult a physician.
- Dosage: Adults: 1-2 drops every 2-4 hours initially, then reduce frequency; Children: Consult pediatrician.
- Monitoring Parameters: Monitor for signs of allergic reactions, worsening infection, or unusual eye irritation.
Popular Combinations
This combination itself is a popular formulation for treating bacterial eye infections. There isn’t enough information available to recommend further combinations. Always consult with an ophthalmologist before combining any eye medications.
Precautions
- General Precautions: Evaluate for allergies, assess renal/hepatic function in specific patient populations.
- Specific Populations:
- Pregnant Women: Consult a doctor before use.
- Breastfeeding Mothers: Consult a doctor before use.
- Children & Elderly: Dosage adjustment may be necessary.
- Lifestyle Considerations: Avoid touching the tip of the bottle to the eye; temporary blurred vision may affect driving.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Boric Acid + Sulphacetamide + Zinc Sulphate Monohydrate?
A: Adults: 1-2 drops in the affected eye(s) every 2-4 hours initially, reducing frequency as infection improves. Children: Consult a pediatrician for appropriate dosing.
Q2: What are the common side effects?
A: Burning or stinging upon instillation, temporary blurred vision, eye irritation, and itching.
Q3: Are there any serious side effects?
A: Rarely, severe allergic reactions or Stevens-Johnson syndrome can occur.
Q4: Can this medication be used during pregnancy or breastfeeding?
A: Consult a doctor before using during pregnancy or while breastfeeding.
Q5: How does this combination drug work?
A: Sulphacetamide inhibits bacterial folic acid synthesis, while boric acid and zinc sulphate have antiseptic properties.
Q6: Are there any drug interactions I should be aware of?
A: Avoid concomitant use with silver nitrate or polyvinyl alcohol-containing eye drops.
Q7: What should I do if my symptoms don’t improve?
A: Consult an ophthalmologist if symptoms worsen or do not improve after a few days of treatment.
A: Remove contact lenses before instilling the drops and wait at least 15 minutes before reinserting them. Avoid using contact lenses if your eyes are infected.
Q9: Can I use this medication if I am allergic to sulfa drugs?
A: No, this medication is contraindicated in individuals with a known hypersensitivity to sulfonamides.
