Chloramphenicol is a bacteriostatic antibiotic with a broad spectrum of activity against both Gram-positive and Gram-negative bacteria, as well as certain other microorganisms. It functions by inhibiting bacterial protein synthesis, specifically by binding to the 50S ribosomal subunit. This mechanism makes it a valuable agent in treating serious infections, particularly when other antibiotics are ineffective or contraindicated. Its use is typically reserved for severe cases due to potential serious adverse effects, underscoring the necessity of medical supervision.

Features

• Broad-spectrum activity against aerobic and anaerobic bacteria
• Effective against Rickettsia, Mycoplasma, and Chlamydia species
• Available in oral, topical, and intravenous formulations
• Rapid absorption and distribution throughout body tissues, including the CNS
• Well-established efficacy in treating meningitis, typhoid fever, and eye infections

Benefits

• Provides rapid clinical response in life-threatening bacterial infections
• Effective penetration into difficult-to-reach sites, including the brain and eyes
• Useful as a second-line treatment when first-line antibiotics fail or are unsuitable
• Cost-effective option in certain healthcare settings
• Available in multiple formulations to suit various clinical needs and infection sites

Common use

Chloramphenicol is primarily indicated for serious infections where less hazardous agents are ineffective or contraindicated. Common uses include bacterial meningitis caused by Haemophilus influenzae, Neisseria meningitidis, or Streptococcus pneumoniae when penicillin cannot be used. It is also employed in the treatment of typhoid fever caused by Salmonella typhi, Rocky Mountain spotted fever, and other rickettsial diseases. Topical formulations are frequently used for eye infections such as bacterial conjunctivitis. In some cases, it may be used for anaerobic infections, particularly those involving Bacteroides fragilis.

Dosage and direction

Dosage varies significantly based on the infection severity, patient age, weight, and renal/hepatic function. For serious systemic infections in adults, the typical intravenous dose is 50-100 mg/kg/day divided every 6 hours, not exceeding 4 g daily. For typhoid fever, 50 mg/kg/day orally in divided doses for 14-21 days is common. Pediatric dosing is weight-based, typically 50-75 mg/kg/day divided every 6 hours. Ophthalmic ointment or solution is generally applied every 3-6 hours to the affected eye. All dosing must be determined by a healthcare provider based on specific clinical circumstances.

Precautions

Regular monitoring of complete blood counts is essential before and during therapy due to risk of bone marrow suppression. Use with caution in patients with hepatic or renal impairment, requiring dosage adjustment. Avoid prolonged use to prevent superinfection or development of resistant organisms. Patients should be advised to report immediately any signs of infection, unusual bleeding, or fatigue. Use during pregnancy only if clearly needed and potential benefits justify potential risks to the fetus.

Contraindications

Hypersensitivity to chloramphenicol or any component of the formulation. Should not be used for trivial infections, prophylaxis, or when less dangerous agents would be effective. Contraindicated in patients with history of chloramphenicol-induced blood dyscrasias. Avoid use in neonates, especially premature infants, due to risk of “gray baby syndrome.”

Possible side effect

• Bone marrow suppression (dose-related reversible anemia or irreversible aplastic anemia)
• Gastrointestinal disturbances (nausea, vomiting, diarrhea)
• Hypersensitivity reactions (rash, fever, angioedema)
• Optic and peripheral neuritis with prolonged use
• Gray baby syndrome in neonates (cardiovascular collapse, cyanosis)
• Superinfections due to alteration of normal flora

Drug interaction

Chloramphenicol may inhibit metabolism of drugs metabolized by CYP2C9 and CYP3A4 enzymes, potentially increasing levels of warfarin, phenytoin, tolbutamide, and chlorpropamide. Concurrent use with other bone marrow suppressants (e.g., chemotherapy drugs) may increase risk of hematologic toxicity. May antagonize bactericidal activity of penicillins and aminoglycosides in some situations. Barbiturates may reduce chloramphenicol levels, while chloramphenicol may prolong the action of barbiturates.

Missed dose

If a dose is missed, it should be taken as soon as remembered unless it is almost time for the next scheduled dose. Do not double the dose to make up for a missed one. Maintain regular dosing intervals to ensure consistent antibiotic levels. Consult healthcare provider for specific guidance regarding missed doses in serious infections.

Overdose

Symptoms may include nausea, vomiting, altered mental status, and cardiovascular collapse. In neonates, gray baby syndrome may occur with characteristic abdominal distension, cyanosis, and vasomotor collapse. Treatment is primarily supportive with immediate discontinuation of the drug. Hemodialysis may be of limited value due to high protein binding. In cases of recent ingestion, gastric lavage may be considered.

Storage

Store at room temperature (15-30°C or 59-86°F) in tight, light-resistant containers. Keep away from moisture and excessive heat. Do not freeze liquid formulations. Oral solutions prepared from powder should be discarded after 14 days. Keep all medications out of reach of children and pets.

Disclaimer

This information is for educational purposes only and does not constitute medical advice. Chloramphenicol is a potent antibiotic with serious potential side effects and should only be used under direct medical supervision. Always consult a healthcare professional for diagnosis and treatment recommendations. Do not self-medicate or share antibiotics with others.

Reviews

“Chloramphenicol remains a critical agent in our antimicrobial arsenal for multidrug-resistant bacterial meningitis. While we respect its toxicity profile, its ability to achieve therapeutic concentrations in the CNS makes it invaluable in specific scenarios.” - Infectious Disease Specialist, 15 years experience

“In ophthalmology, chloramphenicol eye drops continue to be effective for bacterial conjunctivitis in areas where resistance patterns remain favorable. We monitor usage carefully but find it reliably effective.” - Ophthalmologist, 8 years experience

“The risk of aplastic anemia requires careful patient selection and monitoring, but for typhoid fever in certain endemic areas, chloramphenicol still has an important role when newer agents are unavailable.” - Tropical Medicine Physician, 20 years experience