Microbiological evaluation of cefpodoxime proxetil

Cefpodoxime proxetil

A comprehensive profile of cefpodoxime proxetil including the nomenclatures, formulae, elemental composition, appearance, uses, and applications. The methods which were developed for the preparation of the drug substance and their respective schemes are outlined. The physical characteristics of the drug including the ionization constant, solubility, X-ray powder diffraction pattern, differential scanning calorimetry, thermal behavior, and spectroscopic studies are included. The methods which were used for the analysis of the drug substance in bulk drug and/or in pharmaceutical formulations includes the compendial, spectrophotometric, electrochemical and the chromatographic methods. The other studies which was carried out on this drug substance are including the drug stability, pharmacokinetics, bioavailability, drug evaluation, comparison and several compiled reviews. Finally, more than two hundred references are listed at the end of this profile.

New antimicrobial agents

In any discussion of new antimicrobial agents in the 1990s, a warning and a plea are necessary. The spreading emergence of resistance among bacteria raises concerns for the effectiveness of antimicrobial therapy. Penicillin-resistant pneumococci are probably of most significance in pediatrics and are increasing in frequency, in part related to the use of antimicrobial therapy in young children to treat such infections as otitis media. New practice guidelines have suggested the more limited use of antimicrobial agents in treating serious otitis media. When pediatricians do treat, they should select effective agents. Limiting therapy to brief courses with effective and narrow-spectrum agents may be helpful also. Treating long enough to ensure eradication in serious infections is equally important. Methicillin-resistant S aureus are also increasing and are increasingly a concern in community-acquired infections and nosocomial infections. Using topical agents, such as mupirocin, to treat impetigo and other superficial skin infections can limit exposure to systemic agents and may delay the spread of resistance. Vancomycin-resistant enterococcal infections, an infrequent pediatric problem, are most frightening because no alternative therapies are available. Their occurrence is directly related to use of vancomycin in the communities that are affected. Containing the spread of drug-resistant bacteria will likely require a concerted effort by both physicians and the public. The indiscriminate use of antimicrobial agents to treat non-bacterial infections should be contained. The public must be educated to understand that antimicrobial agents are ineffective against viral infections. In the setting of managed care, educating administrators who make practice decisions that cheaper is not always better will be crucial. The issues of day-care infections and spread of potential pathogens must take on increasing attention and methods to decrease infection sought. Curbing inappropriate use of antimicrobial agents will be as important as learning the nuances between new agents.

Comparative evaluation of orally active antibiotics against community-acquired pathogens: a multi-center study in five Mediterranean countries

In 5 Mediterranean countries 7902 pathogens, all isolated in 1992 and 1993 from community-acquired infections, were studied for susceptibility to the following orally active antibiotics: penicillin G, ampicillin, ampicillin + sulbactam, amoxycillin + clavulanic acid (both 2:1 ratio), cefalexin, cefaclor, cefuroxime, cefetamet, doxycycline and erythromycin. Ten centers in Italy, 4 centers in Greece, 3 centers in Spain, and 1 center in Lebanon and Saudi Arabia contributed to this study; all centers used performed standardized microtiter panels (Sceptor, BBL, Heidelberg, FRG). The most frequently isolated pathogens were Escherichia coli (n = 1267), Proteus mirabilis (n = 843), Klebsiella pneumoniae (n = 771), enteric Salmonella spp. (n = 629), Enterobacter cloacae (n = 486), Citrobacter freundii (n = 383), Streptococcus agalactiae (n = 346), Haemophilus influenzae (n = 298), Streptococcus pyogenes (n = 294), Streptococcus pneumoniae (n = 246), Klebsiella oxytoca (n = 243), and Shigella spp. (n = 185). Statistical analysis was performed for each of the above countries and for all pooled data available. The penicillin antibiotics were the most active compounds against the gram-positive cocci, exceeding the MIC90 values 2- to 8-fold over all cephalosporins. Regarding the gram-negatives (above all Klebsiella spp.) cefetamet was by far the most active compound (MIC90 = 1 mg/l). Regarding the percentage of resistant isolates, there were no striking discrepancies between the centers and countries involved in this study. There was, however, complete cross-resistance in penicillin-resistant S. pneumoniae isolates (MIC90 = 2 mg/l). By far the majority of the penicillin-resistant pneumococci showed additional resistance to doxycycline and erythromycin.(ABSTRACT TRUNCATED AT 250 WORDS)

Cefpodoxime proxetil: a new, broad-spectrum, oral cephalosporin

OBJECTIVE

To discuss the chemistry, pharmacokinetics, spectrum of activity, clinical trials, adverse effects, drug interactions, and dosage guidelines of cefpodoxime proxetil.

DATA SOURCES

Literature was identified through a MEDLINE search from 1988 to the present and from review of bibliographies in that literature.

STUDY SELECTION

Data were limited to comparative trials published in the English literature. Although many studies were conducted in Japan, the results often were available only in Japanese or partly in English. As these studies could not be completely evaluated, they are not included in this review.

DATA SYNTHESIS

Cefpodoxime exhibits good activity against many gram-positive and gram-negative organisms. In clinical trials, cefpodoxime was similar in both clinical and bacteriologic efficacy to amoxicillin, cefaclor, amoxicillin/clavulanate, and penicillin in the treatment of respiratory and urinary tract infections. It also appeared effective in the treatment of skin and soft tissue infections, although no comparative trials have been performed. Cefpodoxime is well tolerated by children and is effective in the treatment of otitis media and pharyngitis. It has a similar adverse effect profile to that of other penicillins and cephalosporins, with gastrointestinal effects being most common.

CONCLUSIONS

Cefpodoxime demonstrates good in vitro activity against pathogens frequently associated with respiratory tract, urinary tract, and skin and tissue infections. It has not demonstrated greater efficacy than the other antibiotics to which it has been compared. The available published clinical trials are fraught with methodologic, statistical, and evaluative flaws. Thus, further trials comparing cefpodoxime with established treatments, as well as the newer cephalosporins, are needed before its place in therapy can be established.

Impact of cefpodoxime proxetil and amoxicillin on the normal oral and intestinal microflora

Ten healthy volunteers were given 200 mg cefpodoxime proxetil tablets every 12 h and ten volunteers received 500 mg amoxicillin tablets every 8 h for seven days and the impact of the agents on the oral and intestinal microflora was studied. In the oral microflora, only minor alterations were observed in both groups. In subjects receiving cefpodoxime proxetil, the numbers of streptococci, enterobacteria and clostridia were strongly reduced in the faecal flora, while there was an overgrowth of enterococci, yeasts and Clostridium difficile. Amoxicillin administration induced somewhat smaller alterations in the faecal microflora, although all subjects had overgrowth of new colonizing amoxicillin resistant microorganisms, mainly Escherichia coli, Klebsiella and Enterobacter. Beta-lactamase activity was detected in the flora of six volunteers from each group.