Usage
This combination medication is primarily used for eye infections and injuries. It combines an antibiotic (chloramphenicol), an anti-inflammatory corticosteroid (dexamethasone), a preservative (phenyl mercuric nitrate), and another antibiotic (polymyxin B). This combination addresses bacterial infection, reduces inflammation, and aids in healing.
Pharmacological Classification:
- Chloramphenicol: Antibiotic (bacteriostatic)
- Dexamethasone: Corticosteroid (anti-inflammatory, immunosuppressant)
- Phenyl Mercuric Nitrate: Antiseptic, preservative
- Polymyxin B: Antibiotic (bactericidal)
Alternate Names
There is no internationally recognized non-proprietary name for this specific combination. It’s typically referred to by the constituent drug names. Brand names vary depending on the manufacturer and region.
How It Works
Chloramphenicol: Inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit, preventing peptide bond formation. It is primarily bacteriostatic. Metabolized mainly by the liver and excreted renally.
Dexamethasone: A synthetic glucocorticoid that exerts its anti-inflammatory and immunosuppressive effects by binding to glucocorticoid receptors. This binding modulates gene expression, affecting various physiological processes like inflammation, immune response, and metabolism. Metabolized primarily in the liver and excreted in the urine.
Phenyl Mercuric Nitrate: Acts as a preservative and antiseptic. It disrupts the cell membrane of microorganisms, leading to their inactivation. Its pharmacokinetics are not extensively studied.
Polymyxin B: A bactericidal antibiotic that acts by disrupting the bacterial cell membrane permeability. It binds to the lipid A portion of lipopolysaccharide in the outer membrane of Gram-negative bacteria, leading to leakage of cellular contents and cell death. Primarily excreted renally.
Dosage
Dosage depends on the specific product formulation and the severity of the condition. Always follow the instructions provided by the physician or on the product packaging.
Standard Dosage
Adults: Usually, one or two drops are instilled into the affected eye(s) every few hours, as directed by the physician.
Children: Dosage in children should be determined and supervised by a physician, and it usually involves a reduced frequency or concentration compared to the adult dose.
Special Cases: Dosage adjustments might be necessary in elderly patients, those with renal or hepatic impairment, or with certain comorbid conditions. Consult a specialist in such situations.
Clinical Use Cases
This combination isn’t typically used in the listed clinical settings (intubation, surgical procedures, mechanical ventilation, ICU use, emergency situations). It’s primarily for topical ophthalmic use.
Side Effects
Common Side Effects
Transient burning or stinging, temporary blurred vision, eye irritation, redness.
Rare but Serious Side Effects
Allergic reactions (itching, swelling, severe redness), signs of increased intraocular pressure (eye pain, headache, nausea, vomiting), persistent blurred vision.
Long-Term Effects
Long-term use of topical corticosteroids like dexamethasone can increase the risk of cataracts, glaucoma, and secondary eye infections.
Adverse Drug Reactions (ADR)
Severe allergic reactions, vision changes, signs of systemic corticosteroid effects (uncommon with ophthalmic use but possible with prolonged or high-dose use).
Contraindications
Hypersensitivity to any of the components, viral or fungal eye infections, untreated purulent eye infections, deep keratitis.
Drug Interactions
Other ophthalmic medications may interact with this combination. Inform your physician about all other medications being used.
Pregnancy and Breastfeeding
Consult a physician before use during pregnancy or breastfeeding. The safety profile for this specific combination in these situations is not well-established.
Drug Profile Summary
- Mechanism of Action: See detailed explanation above.
- Side Effects: See detailed explanation above.
- Contraindications: Hypersensitivity, viral/fungal eye infections.
- Drug Interactions: Consult with a physician about concomitant ophthalmic medications.
- Pregnancy & Breastfeeding: Consult a physician before use.
- Dosage: Varies depending on the specific product. See the instructions.
Popular Combinations
This particular combination is itself a common formulation.
Precautions
As described above.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Chloramphenicol + Dexamethasone + Phenyl Mercuric Nitrate + Polymyxin B?
A: The dosage depends on the specific product and the condition being treated. Consult the physician or product information for specific instructions.
Q2: What are the common side effects?
A: Common side effects include temporary burning, stinging, blurred vision, and eye irritation.
Q3: Can I use this if I’m allergic to other antibiotics?
A: If you have any known drug allergies, inform your physician before using this combination.
A: Contact lenses should generally be avoided while using ophthalmic medications unless specifically advised by a physician.
Q5: What should I do if I experience severe eye pain after using the drops?
A: Discontinue use and immediately consult your physician.
Q6: Can pregnant or breastfeeding women use this combination?
A: Consult a physician before use during pregnancy or breastfeeding.
Q7: How long should I use these eye drops?
A: Use this medication for the duration prescribed by your physician. Do not discontinue use prematurely even if symptoms improve.
Q8: What should I do if I miss a dose?
A: Instill the missed dose as soon as you remember, unless it’s close to the time for the next dose. Do not double the dose.
Q9: Can this be used for ear infections?
A: This combination is specifically formulated for ophthalmic use (eye infections) and is not suitable for ear infections. Consult a physician for appropriate treatment for ear infections.
