Pharmacology chloramphenicol

Pharmacology Chloramphenicol binds to 50 S ribosomal subunits of bacteria and interferes with or inhibits protein synthesis. 

P-Nitro alcohols can be hydrogenated to the corresponding amino alcohols with retention of configuration the stereoselective Henry reaction is a useful tool in the elaboration of pharmacologically important P-amino alcohol derivatives including chloramphenicol, ephedrine, norephedrine, and others. Some important P-amino alcohols are listed in Scheme 3.11.107... 

Basic and Clinical Pharmacology > Chapter 44. Tetracyclines. Macrolides. Clindamycin. Chloramphenicol. Streptogramins, Oxazolidinones > ... 

Chloramphenicol. The broad-spectrum antibiotic chloramphenicol is completely absorbed after oral ingestion. It undergoes even distribution in the body and readily crosses diffusion barriers such as the blood-Luellmann, Color Atlas of Pharmacology 2005 Thieme All rights reserved. Usage subject to terms and conditions of license. 

Some ADRs are caused by most or all medications in a class, while others are agent specific. Nausea, vomiting, and diarrhea have been observed with most antibiotics, yet only chloramphenicol and certain sulfonamide antibiotics have been consistently implicated as causes of aplastic anemia. Some pharmacological effects, such as sedation from an antihistamine, may be considered adverse effects when they are... 

Sande, M.A. Mandell, G.L. Antimicrobial agents tetra-cyline, chloramphenicol, erythromycin, and miscellaneous antibacterial agents. In Pharmacological Basis of Therapeutics, 8th Ed. Gilman, A.G., Rail, T.W., Nies, A.S., Taylor, P., Eds. Pergamon Press New York, 1991 1117-1145. 

An interaction of warfarin with ocular chloramphenicol (5 mg/ml 1 drop qds in each eye), which led to an increase in INR, has been suspected in an 83-year-old white woman (83). The authors suggested that the effect may be due to chloramphenicol inhibition of hepatic microsomal CYP2C9, since the pharmacologically active enantiomer 5-warfarin is metabolized by this enzyme). 

Krasinski K, Kusmiesz H, Nelson JD. Pharmacologic interactions among chloramphenicol, phenytoin and pheno-barbital. Pediatr Infect Dis 1982 l(4) 232-5. 

Sulfites, including potassium metabisulfite, can react with various pharmaceutical compounds including sympathomi-metics such as epinephrine (adrenaline), chloramphenicol, cisplatin, and amino acids, which can result in their pharmacological inactivation. Sulfites are also reported to react with phenylmercuric nitrate, and may adsorb onto rubber closures. 

Nahata MC (1989) Lack of predictability of chloramphenicol toxicity in pediatric patients. Journal of Clinical Pharmacology and Therapeutics 14 297-303. 

Mertin D and Lippold BC (1997) In-vitro permeability of the human nail and of a keratin membrane from bovine hooves Penetration of chloramphenicol from lipophilic vehicles and a nail lacquer. The Journal of Pharmacy and Pharmacology 49 241-245. 

Reiche, R., Mulling, M. Frey, H.-H. (1980) Pharmacokinetics of chloramphenicol in calves during the first weeks of life. Journal of Veterinary Pharmacology and Therapeutics, 3, 95-106. 

Adverse events are sometimes termed type A (usually pharmacologically predictable, relatively frequent, seldom fatal and usually identified during clinical trials) or type B (unpredictable idiosyncratic reactions which are usually infrequent but can be very serious or fatal) (Rawlins and Thompson, 1977 Venning, 1983). Postmarketing ADR monitoring usually identifies the more serious, type B reactions. The sample size needed in clinical trials to detect differences between an incidence rate of 1/10 000 and 2/10 000 is about 306 000 patients (e.g. for a placebo comparison of chloramphenicol-induced aplastic anemia, which occurs in 1/30 000 Lasagna, 1983). Clinical trials at this scale are simply impractical. 

Figure 44-2. Steps in protein synthesis and sites of action of (1) chloramphenicol (2) macrolides and clindamycin and (3) tetracyclines. The 70S ribosomal mRNA complex is shown with its SOS and SOS subunits. The peptidyl-tRNA at the donor site donates the growing peptide chain to the aminoacyl-tRNA at the acceptor site in a reaction catalyzed by peptidyl transferase. The tRNA, discharged of its peptide, is released from the donor site to make way for translocation of the newly formed peptidyl-tRNA. The acceptor site is then free to be occupied by the next "charged aminoacyl-tRNA. See text for additional details. (Reproduced, with permission, from Katzung BG [editor] Basic Clinical Pharmacology, 8th ed. McGraw-Hill, 2001.)...

Papich MG, Riviere JE, Chloramphenicol and derivatives, macrolides, lincosamides and miscellaneous antimicrobials, in Riviere JE, Papich MG, eds.. Veterinary Pharmacology and Therapeutics, 9th ed., Wiley-Blackwell, Iowa State Univ. Press, Ames 2009 945-982. 

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