Chloromycetin (chloramphenicol) is a bacteriostatic antibiotic with a well-established history in clinical practice, valued for its broad-spectrum activity against both Gram-positive and Gram-negative bacteria, as well as certain other microorganisms. Its mechanism of action involves inhibition of bacterial protein synthesis by binding to the 50S ribosomal subunit, making it a critical agent in managing serious infections where other antibiotics may be ineffective. While its use is now carefully restricted due to potential serious adverse effects, it remains an essential therapeutic option in specific clinical scenarios under strict medical supervision.

Features

• Active ingredient: Chloramphenicol
• Available forms: Oral capsules, ophthalmic preparations, topical formulations
• Bacteriostatic action against a wide range of pathogens
• Good tissue penetration, including central nervous system
• Multiple administration routes depending on infection type
• Well-characterized pharmacokinetic profile

Benefits

• Effective against multidrug-resistant organisms where other antibiotics fail
• Rapid bacterial load reduction in susceptible infections
• Crosses blood-brain barrier, making it valuable for CNS infections
• Available in various formulations for targeted treatment approaches
• Cost-effective option in resource-limited settings for specific indications
• Established clinical efficacy with decades of real-world use data

Common use

Chloromycetin is primarily indicated for serious infections caused by susceptible organisms when less potentially dangerous agents are ineffective or contraindicated. Its use includes treatment of typhoid fever, bacterial meningitis, rickettsial diseases, and certain anaerobic infections. In ophthalmology, it’s used for superficial ocular infections involving the conjunctiva or cornea. Topical formulations are employed for skin infections and burns. The drug is particularly valuable in cases of Haemophilus influenzae meningitis, especially in penicillin-allergic patients, and for infections caused by Bacteroides fragilis.

Dosage and direction

Dosage must be individualized based on infection severity, patient age, renal function, and susceptibility of causative organisms. For systemic infections in adults: 50 mg/kg/day divided into 4 equal doses, not to exceed 4 g daily. For children: 50-75 mg/kg/day in divided doses. For ophthalmic use: Apply 1-2 drops to affected eye every 3-6 hours. Topical application: Apply thin layer to affected area 1-3 times daily. Treatment duration should be the shortest possible to achieve cure, typically 5-14 days depending on infection type and response. Complete the full course even if symptoms improve earlier.

Precautions

Regular monitoring of complete blood counts is mandatory before and during therapy due to risk of bone marrow suppression. Use with extreme caution in patients with hepatic or renal impairment requiring dosage adjustment. Avoid concurrent use with other myelosuppressive drugs. Monitor serum concentrations when possible, maintaining peak levels between 10-20 mcg/mL and trough levels below 15 mcg/mL. Use protective measures during preparation and administration to avoid exposure. Pregnancy Category C: Use only if potential benefit justifies potential risk to fetus.

Contraindications

Hypersensitivity to chloramphenicol or any component of the formulation. History of chloramphenicol-induced blood dyscrasias. Concomitant use with drugs that potentially cause bone marrow suppression. Prophylactic use in trivial infections. Treatment of minor infections or as first-line therapy when other effective agents are available. Patients with genetic predisposition to blood disorders. Neonates due to potential for “gray baby syndrome.”

Possible side effect

The most serious adverse effect is bone marrow suppression, which may be dose-related and reversible or idiosyncratic and potentially fatal. Hematologic: Aplastic anemia, thrombocytopenia, leukopenia. Gastrointestinal: Nausea, vomiting, diarrhea. Neurologic: Optic neuritis, peripheral neuropathy. Other: Gray baby syndrome in neonates, hypersensitivity reactions, superinfections. Ophthalmic use may cause transient burning, stinging, or blurred vision. Topical application may cause local irritation, rash, or angioedema.

Drug interaction

Chloromycetin interacts significantly with multiple drug classes. It may inhibit metabolism of warfarin, phenytoin, tolbutamide, and chlorpropamide, increasing their effects and toxicity. Concurrent use with other myelosuppressive agents (cytotoxic drugs, zidovudine) increases hematologic toxicity. Barbiturates and rifampin may decrease chloramphenicol levels. May antagonize bactericidal activity of penicillins and aminoglycosides in some infections. Alcohol may cause disulfiram-like reaction.

Missed dose

If a dose is missed, take it as soon as remembered unless it’s almost time for the next dose. Do not double the dose to make up for a missed one. Maintain regular dosing intervals to ensure consistent therapeutic levels. If multiple doses are missed, contact healthcare provider for guidance on resuming therapy. For ophthalmic preparations, apply the missed dose when remembered unless the next dose is due within an hour.

Overdose

Symptoms include nausea, vomiting, altered mental status, and cardiovascular collapse. In infants, gray baby syndrome may occur with abdominal distension, cyanosis, and circulatory collapse. Management involves immediate discontinuation, supportive care, and symptomatic treatment. Charcoal hemoperfusion may enhance elimination. No specific antidote exists. Monitor complete blood counts frequently for several weeks post-overdose. Maintain adequate hydration and electrolyte balance.

Storage

Store at controlled room temperature (15-30°C) in tight, light-resistant containers. Keep away from moisture and excessive heat. Do not freeze. Keep all medications out of reach of children and pets. Discard any unused portion after completion of therapy or if beyond expiration date. Do not transfer capsules to other containers. Ophthalmic solutions should be discarded 28 days after opening.

Disclaimer

This information is for educational purposes only and does not constitute medical advice. Chloromycetin is a potent antibiotic with serious potential adverse effects and must be used only under direct medical supervision with appropriate monitoring. Never self-medicate with this drug. Always follow your healthcare provider’s instructions regarding dosage, duration, and monitoring requirements. Report any unusual symptoms or side effects immediately to your physician.

Reviews

“Chloromycetin remains a vital antibiotic in our infectious disease arsenal, particularly for multidrug-resistant Salmonella typhi infections. However, its use requires meticulous hematological monitoring and should be reserved for cases where benefits clearly outweigh risks.” - Infectious Disease Specialist, 15 years experience

“In ophthalmology, chloramphenicol drops are effective for bacterial conjunctivitis, though we now prefer newer agents with better safety profiles for routine cases. It still has value in specific situations where cost is a major factor.” - Ophthalmologist, teaching hospital

“The risk of aplastic anemia, though rare, necessitates extreme caution. We maintain strict protocols for patient selection, monitoring, and duration of therapy. It’s not a drug to be used lightly.” - Clinical Pharmacologist