Chloromycetin (chloramphenicol) is a bacteriostatic antibiotic with a well-established history in treating serious bacterial infections when other antibiotics are ineffective or contraindicated. Its broad-spectrum activity covers both Gram-positive and Gram-negative bacteria, including anaerobic organisms, making it a critical option in specific clinical scenarios. This antibiotic works by inhibiting bacterial protein synthesis at the ribosomal level, effectively halting microbial proliferation. While its use is reserved due to potential serious adverse effects, it remains an indispensable therapeutic agent in certain infectious diseases under careful medical supervision.

Features

• Active ingredient: Chloramphenicol
• Available formulations: Oral capsules, ophthalmic preparations, topical creams, and intravenous solutions
• Mechanism of action: Inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit
• Spectrum: Broad-spectrum activity against aerobic and anaerobic Gram-positive and Gram-negative bacteria
• Stability: Chemically stable in various formulations with defined shelf-life

Benefits

• Effective against multidrug-resistant organisms where first-line antibiotics fail
• Rapid tissue penetration, achieving therapeutic concentrations in hard-to-reach sites including the CNS and eyes
• Bacteriostatic action that allows the immune system to协同清除病原体
• Available in multiple formulations for targeted treatment approaches
• Cost-effective alternative for specific serious infections in resource-limited settings

Common use

Chloromycetin is primarily indicated for serious infections caused by susceptible organisms when less dangerous alternatives are ineffective or contraindicated. These include bacterial meningitis caused by Haemophilus influenzae, rickettsial diseases such as typhus fever, and other severe infections where the benefit outweighs the risk. It is also used topically for eye infections including bacterial conjunctivitis, and in veterinary medicine. Its systemic use is generally restricted to hospitalized patients under close monitoring due to the risk of serious adverse effects.

Dosage and direction

Dosage must be individualized based on the infection severity, patient’s age, weight, renal function, and formulation used. For adults with serious infections: 50-100 mg/kg/day divided every 6 hours, not to exceed 4 g daily. Pediatric dosing requires careful calculation based on body weight and close monitoring. Ophthalmic formulation: Apply 1-2 drops to affected eye(s) every 3-6 hours initially, then reduce frequency as infection improves. Oral administration should occur 1 hour before or 2 hours after meals for optimal absorption. Treatment duration typically ranges from 5-14 days depending on infection type and response.

Precautions

Complete blood counts must be monitored 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 unnecessary use as it may promote bacterial resistance. Pregnancy Category C: Use only if potential benefit justifies potential risk to fetus. Nursing mothers should discontinue breastfeeding during treatment as chloramphenicol is excreted in human milk. Not recommended for prophylaxis of bacterial infections or treatment of minor infections.

Contraindications

Hypersensitivity to chloramphenicol or any component of the formulation. Patients with history of chloramphenicol-induced blood dyscrasias. Avoid concurrent use with drugs that suppress bone marrow function. Contraindicated in the treatment of trivial infections, colds, influenza, or as prophylactic agent. Should not be used in patients with glucose-6-phosphate dehydrogenase deficiency due to risk of hemolytic anemia.

Possible side effect

The most serious adverse effect is bone marrow suppression, which may be dose-related and reversible or idiosyncratic and fatal (aplastic anemia). Gastrointestinal disturbances including nausea, vomiting, diarrhea. Neurotoxic reactions: optic neuritis, peripheral neuritis, headache. Gray baby syndrome in neonates: abdominal distension, cyanosis, vasomotor collapse. Hypersensitivity reactions: rash, fever, angioedema. Superinfections with nonsusceptible organisms. Hematologic: leukopenia, thrombocytopenia, granulocytopenia.

Drug interaction

Potentiates effects of oral anticoagulants requiring reduced warfarin dosage. Concurrent use with phenytoin may increase phenytoin levels and toxicity. May antagonize bactericidal activity of penicillins and aminoglycosides. Drugs that induce hepatic enzymes (rifampin, phenobarbital) may decrease chloramphenicol levels. Alcohol may cause disulfiram-like reaction. Concurrent use with other bone marrow suppressants (cytotoxic drugs, zidovudine) increases hematologic toxicity risk.

Missed dose

If a dose is missed, take it as soon as remembered unless it is almost time for the next dose. Do not double the dose to make up for the missed one. Maintain regular dosing intervals to ensure consistent therapeutic blood levels. If multiple doses are missed, contact healthcare provider for guidance on resumption of therapy.

Overdose

Symptoms include nausea, vomiting, altered mental status, gray baby syndrome in infants. Cardiovascular collapse may occur. Treatment is supportive with gastric lavage if recent ingestion. Charcoal hemoperfusion may be beneficial. No specific antidote exists. Monitor complete blood counts frequently for several weeks after overdose due to delayed bone marrow toxicity.

Storage

Store at controlled room temperature (15-30°C or 59-86°F). Protect from light and moisture. Keep ophthalmic solutions sterile and discard 28 days after opening. Do not freeze liquid formulations. Keep all medications out of reach of children. Properly discard expired medication according to local regulations.

Disclaimer

This information is for educational purposes only and does not constitute medical advice. Chloromycetin is a prescription medication that must be used under direct medical supervision. Healthcare professionals should consult official prescribing information before administration. Patients should not self-medicate with this antibiotic due to serious potential adverse effects.

Reviews

“Chloromycetin remains our go-to antibiotic for multidrug-resistant typhoid fever in endemic areas. While we monitor blood counts rigorously, its efficacy in serious cases is unmatched.” - Infectious Disease Specialist, 15 years experience

“Used chloramphenicol eye drops for severe bacterial conjunctivitis unresponsive to other antibiotics. Complete resolution within 72 hours with proper dosing.” - Ophthalmologist

“Despite its risks, chloramphenicol saved my patient with vancomycin-resistant enterococcal meningitis when all other options failed. Careful monitoring is essential.” - Neurologist

“The hematologic toxicity concerns limit its use, but in selected cases with no alternatives, chloramphenicol proves its worth as a life-saving antibiotic.” - Clinical Pharmacist