Spectra penicillins

There are four groups of penicillins natural penicillins, penicillinase-resistant penicillins, aminopeni-cillins, and the extended-spectrum penicillins. See the... 

When used for intraabdominal infection, aminoglycosides should be combined with agents that are effective against the majority of B. fragilis. Clindamycin or metronidazole is the agent of first choice, but others, such as antianaerobic cephalosporins (e.g., cefoxitin, cefotetan, or ceftizoxime), piperacillin, mezlocillin, and combinations of extended-spectrum penicillins... 

Cirrhosis Peritoneal Cefotaxime Regimen based on organism isolated 1. Add clindamycin or metronidazole if anaerobes are suspected 2. Other third-generation cephalosporins, extended-spectrum penicillins, aztreonam, and imipenem as alternatives 3. Aminoglycoside with antipseudomonal penicillin... 

Other Imipenem/cilistatin, meropenem, ertapenem, or extended-spectrum penicillins with B-lactamase inhibitor 1. Ciprofloxacin with metronidazole 2. Aztreonam with clindamycin or metronidazole 3. Antianaerobic cephalosporins.3... 

These agents are generally effective for susceptible bacteria. The extended-spectrum penicillins are more active against P. aeruginosa and enterococci and are preferred over cephalosporins. They are very useful in renally impaired patients or when an aminoglycoside is to be avoided. 

A recent prospective study of AAD and CDAD in five Swedish hospitals showed an increased risk of AAD with cephalosporins, clindamycin and broad-spectrum penicillins [42], While CDAD is well recognized as the most common nosocomial gastrointestinal pathogen, some... 

Pseudomonas Cephtazidime, cefepime, imipenem, aztreonatn, ciprofloxacin, aminoglycoside, and extended-spectrum penicillin... 

The answer is b. (Hardman, p 1077.) Unlike the other listed drugs, oxacillin is resistant to penicillinase. The other four agents are broad-spectrum penicillins, while oxacillin is generally specific for Gram-positive microorganisms Use of penicillinase-resistant penicillins should be resewed for infections caused by penicillinase-producing staphylococci... 

Other third-generation cephalosporins, extended-spectrum penicillins, aztre-onam, and imipenem as alternatives... 

Antianaerobic cephalosporins or extended-spectrum penicillins are effective in preventing most infectious complications after acute bacterial contamination, such as with abdominal trauma where GI contents enter the peritoneum, and when the patient is seen soon after injury (within 2 hours) and surgical measures are instituted promptly. 

Monotherapy with imipenem 0.5 g IV every 6-8 hours, meropenem 1 g IV every 8 hours, ertapenem 1 g IV every 24 hours, extended-spectrum penicillins with a /3-lactamase inhibitor (piperacillin/tazobactam 4.5 g IV every 6 hours), or tigecycline 100 mg IV as loading dose, then 50 mg IV every 12 hours... 

Complicated coli Proteus mirabiiis Klebisella pneumoniae Pseudomonas aeruginosa Enterococcus faecalis 1. Quinolone x 14 days (B, III)0 2. Extended-spectrum penicillin plus aminoglycoside (B, III)0 Severity of illness will determine duration of IV therapy culture results should direct therapy Oral therapy may complete 14 days of therapy... 

Penicillinacylase is used industrially to catalyze the hydrolytic removal of the side chain in naturally occurring penicillins such as benzylpenicillin (4.49) and phenoxymethylpenicillin (4.50). The nucleus 6-aminopenicillic acid (4.48) is then used as the starting material for the preparation of semisynthetic penicillins. Appropriate acylation of the 6-NH2 group leads to )3-lactamase-stable and broad-spectrum penicillins. 

Amoxicillin is a broad spectrum penicillin antibiotic. Antibiotics tend to cause pseudomembranous colitis as a result of colonisation of the colon by Clostridium difficile following antibiotic therapy. 

Cystic fibrosis Cystic fibrosis patients have a higher incidence of side effects (eg, fever, rash) when treated with extended-spectrum penicillins (eg, piperacillin, carbenicillin). 

Obstetric infections can be treated with penicillin-beta-lactamase inhibitors such as amoxicillin-clavulanic acid, with extended spectrum penicillins (with or without beta-lacamase inhibitors if justified by local resistance surveillance data), with a first or second generation cephalosporin combined with metronidazole. In severe cases of streptococcal infection high doses of penicillin in combination with clindamycin is the treatment of choice. In amnionitis, maternal morbidity resolves with delivery. In endometritis, antibiotics should be stopped after the... 

Broad spectrum therapy is started on an empirical basis. Intra-abdominal infections can be treated by ampicillin (or amoxycillin) or clindamycin combined with aminoglycosides, penicillin-beta-lacta-mase inhibitors such as amoxycillin-clavulanic acid or a second or third generation cephalosporin combined with metronidazole are good alternatives. In patients with impaired immunity and/or prior use of antibiotics, i.e. when it is reasonable to expect resistant pathogens, a broad spectrum penicillin plus beta-lactamase inhibitor or a carbapenem can be used empirically in monotherapy. In septic patients, the rapidly bactericidal action of aminoglycosides is useful. Aminoglycosides should preferentially not be given for more than 3-5 days. 

COPD exacerbations. Therefore, in exacerbation treatment with antibiotics is justified when the patient has at least two of three features of increased dyspnea, increased sputum volume, and sputum pu-rulence. Antibiotic choice will depend on local experience derived from local bacteriological sensitivity data. Older, less costly compounds such as tetracycline, doxycycline, amoxicillin, erythromycin, cefaclor etc. are often as effective as newer, more expensive ones. If resistant organisms are suspected or when the severity of the patients clinical condition puts them at high-risk of treatment failure, a second or third generation cephalosporin, fluoroquinolone, newer macrolide or broad-spectrum penicillin may be preferred. In cases of recurrent infection prolonged courses of antibiotics continuous or intermittent, may be useful. 

Figure 1.6 Number of antibiotic prescriptions per 1000 inhabitants per antibiotic anatomical therapeutic chemical (ATC) classification in 13 European countries in 1997. In parentheses are the ATCs used by the WHO. Tet = tetracyclines, Pen = penicillin, Ex-Pen = extended-spectrum penicillins, B-Lac = (3-lactamase-sensitive penicillins. Cep = cephalosporins, TMP = trimethoprim (alone or in combination), Mac + Lin = macrolides and lincosamides, Mac = macrolides, Lin = lincosamides. Ami = aminoglycosides, and Qui = quinolone. The 13 countries are SP = Spain, GR = Greece, BG = Belgium, PR = Prance, PL = Portugal, IT = Italy, PI = Pinland, UK = United Kingdom, DE = Denmark, AU = Austria, GE = Germany, SW = Switzerland, and NL = Netherlands. (Based on data from Molstad et al., 2002.)...

Generally replaced by the aminoglycosides or extended-spectrum penicillins for serious infections still used for bladder irrigation and gut decontamination used in combination wit hot her antibiotics and/or corticosteroids topically to treat infections of the eye and skin... 

It is a broad spectrum penicillin which is not destroyed by gastric acid but is penicillinase susceptible. It is more effective than benzyl penicillin against a variety of gram negative microorganisms. 

Extended-Spectrum Penicillins (Ampicillin and the Antipseudomonal Penicillins)... 

Penicillin is rapidly excreted by the kidneys small amounts are excreted by other routes. About 10% of renal excretion is by glomerular filtration and 90% by tubular secretion. The normal half-life of penicillin G is approximately 30 minutes in renal failure, it may be as long as 10 hours. Ampicillin and the extended-spectrum penicillins are secreted more slowly than penicillin G and have half-lives of 1 hour. For penicillins that are cleared by the kidney, the dose must be adjusted according to renal function, with approximately one fourth to one third the normal dose being administered if creatinine clearance is 10 mL/min or less (Table 43-1). 

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