Benzylpenicillin procaine

Pen (Wyeth-Ayerst)-(penicillin V potassium) Pfizerpen G (Pfizer)-(penicillin G potassium) Sugracillin (Upjohn) Wycillin (Wyeth-Ayerst)-(procaine-benzylpenicillin)... 

Procaine benzylpenicillin 156 with solid oxalic acid... 

Synonyms. Benzylpenicillin Novocaine Penicillin G Procaine Procaine Benzylpenicillin Procaine Penicillin G. 

Elimination of the penicillins is primarily via the kidneys, by glomerular filtration and active tubular secretion. The half-life is approximately 1 h after i.v. injection. Because of slow absorption from the injection site, the half-life of procaine benzylpenicillin (procaine penicillin) is approximately 7h. 

Adverse CNS effects occur when the procaine portion of the procaine benzylpenicillin (procaine penicillin) formulation is given intravascularly. The signs of toxicity include hyperexcitability, muscle tremors, ataxia, apnea and cardiac arrest. There is no specific treatment for procaine toxicity one can only attempt to prevent the horse from injuring itself and others imtil the effects of the procaine wear off. The CNS reaction can be prevented by pretreatment with diazepam. The solubility of the procaine fraction of procaine benzylpenicillin (procaine penicillin) formulations increases with increasing ambient temperature, so these products should be stored in a cool place to reduce the risk of reactions. Procaine is a common cause of positive drug tests in racehorses and other performance horses. Procaine benzylpenicillin (procaine penicillin) should be avoided in these animals. 

Procaine benzylpenicillin (procaine penicillin) is a poorly soluble salt that is absorbed slowly following i.m. or s.c. injection. It is the most commonly used formulation of penicillin in horses. Injections s.c. cause severe local inflammation and hemorrhage, as well as leaving deposits of... 

Benzathine benzylpenicillin is a very insoluble salt. It is administered i.m. in "long-acting" formulations that contain one-half procaine benzylpenicillin (procaine penicillin) and one-half benzathine benzylpenicillin. Any clinical effect is from the procaine benzylpenicillin (procaine penicillin) portion of these formulations since the benzathine penicillin provides persistent but sub-therapeutic plasma concentrations. 

Phenothiazines may decrease the seizure threshold in small animal patients and are contraindicated in dogs and cats with seizure disorders. Although in the horse, seizure disorders are rare (see Ch. 9) and the influence of these drugs on the seizure threshold is unknown, the phenothiazines should be avoided in horses with a history of seizures. Phenothiazines are also contraindicated in animals recently exposed to organophosphate insecticides because of the potential to enhance the toxicity to these drugs (Fernandez et al 1975). In addition, the concomitant administration of phenothiazines and procaine or procaine benzylpenicillin is not advised because of the potential to enhance the adverse effects of procaine (Chapman et al 1992). 

Penicillin G, benzathine and procaine (benzylpenicillin, benzathine and procaine) 9000 -16 80Qt U/kg, every 48-96 h i.m. 

Penicillin G, procaine (benzylpenicillin, procaine) 6600 -16000 U/kg, once daily i.m. 

However, in contrast a report claims that antibacterial antagonism was not seen in 65 of 66 patients given chloramphenicol and benzylpenicillin for bronchitis or bronchopneumonia. Ampicillin with chloramphenicol is more effective than chloramphenicol alone in the treatment of typhoid, and in a study of 700 patients, procaine benzylpenicillin with chloramphenicol was shown to be more effective than chloramphenicol alone in the treatment of gonorrhoea (failure rates of 1.8% compared with 8.5%). ... 

A study in patients given intramuscular procaine benzylpenicillin 2.4 or 4.8 million units with or without probenecid 2 g found the peak serum levels were higher in patients given probenecid, but because of wide interpatient variation, possibly associated with differences in the release of penicillin from the injection sites, the exact potentiating effect of probenecid could not be determined. However, another study in men and women given procaine benzylpenicillin 2.4 million units and 4.8 million units, respectively (for uncomplicated gonorrhoea), found treatment failure after 1 week in 15.4% of men and 10.4% of women. Failure rates were reduced to 1.8% and 3.7%, respectively, when oral probenecid 1 g was given with the penicillin."... 

Another report about the treatment of pneumococcal meningitis with intramuscular or intravenous penicillin and intravenous tetracyclines (chlo-rtetracycline, oxytetracycUne, tetracycline) confirmed that the mortality was much lower in those given only penicillin, rather than the combination of penicillin and a tetracycline. fri the treatment of scarlet fever (Group A beta-haemolytic streptococci), no difference was seen in the initial response to treatment with penicillin (oral procaine benzylpenicillin) and chlortetracycUne or the penicillin alone, but spontaneous re-in-feetion occurred more frequently in those who had received both antibacterials. ... 

The principal penicillins of present importance are benzylpenicillin sodium or potassium salt (penicillin G) procaine benzylpenicillin benzathine penicillin benethamine penicillin phenoxymethylpenicillin, potassium or calcium salt (penicillin V) methicillin sodium phenethicillin sodium penicillamine hydrochloride. 

Procaine Benzylpenicillin, C 6Hi804N 2S,Ci3H o02N2,H20, Mol. Wt. 588-7. This salt is composed of one molecule of procaine base and one molecule of benzylpenicillin with one molecule of water of crystallisation. The assay of procaine presents no serious difficulties. Although nitrite titration has been recommended the simplest method is titration with standard acid after alkaline chloroform extraction. 

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