Sub-generation cephalosporins
first generation:
Cephalothin (Vanguard ADM on the 1st)
cefotaxime pyridine (pioneer on the 2nd)
cephalexin (pioneer on the 4th)
cefazolin (Pioneer 5)
Cephradine (Pioneer 6)
cefadroxil
role in the clinical characteristics of the application.
1. nephrotoxicity in the second and third generation large.
2. within the first amine of B-stable enzyme, less than the second and third generations.
3. mainly for drug-resistant and susceptible strains of Staphylococcus aureus infections caused by respiratory tract, urinary tract infections.
second generation:
Meng many cephalosporins (cephalosporins hydroxyl yl)
cefuroxime (Zinacef, cefuroxime)
cefaclor (cephalosporins chlorine ampicillin).
Cefonicid role of sodium
features applications.
1. against Gram-positive bacteria slightly worse than a generation younger brother, against Gram-negative bacteria to do with obvious enhanced, some anaerobic bacteria and efficient.
2. within the first amine of B-enzyme is more stable.
3. toxin than the first generation of the small kidney.
4. mainly due to susceptible strains of the respiratory tract, biliary tract and urinary tract infections.
cefoxitin sodium effect is similar to second-generation cephalosporin is the second-generation cephalosporin cefprozil
third generation:
Cefixime Cefotaxime
ceftriaxone (bacteria must rule)
ceftazidime (Fortum)
cefoperazone (Pioneer will prime)
cefetamet
Cefminox
role of the characteristics apply,
1. of anaerobic and Gram-negative bacteria stronger (including ketones green Pseudomonas) against Gram-positive bacteria is less than one second.
2. within the first amine of B-enzyme is more stable.
3. almost no renal toxicity
4. mainly for serious infections caused by susceptible strains such as urinary tract, pneumonia, meningitis, sepsis, and Pseudomonas aeruginosa infection. The
fourth generation:
cefpirome
cefepime
1. broad-spectrum, high efficiency, some Gram-negative and-positive bacteria have a stronger antibacterial effect.
2. on the B-enzyme stability within the first highest amine.
3. no renal toxicity.
4. mainly used for refractory infection.
*********************************************** ******************< br> cephalosporin cephalosporin by the crown of culture medium isolated cephalosporin C, by obtained a semi-synthetic cephalosporin class of ene nucleus of β-lactam antibiotics.
the penicillin class of drugs with similar effect, are acting on the antibacterial effect of PBP sky. However, the combination of various drugs PBP is different, so there are differences in the anti-bacterial properties.
sub-generation cephalosporin, is based on the age and development of anti-bacterial function, generation of cephalosporins can be divided into the following:
first-generation cephalosporins: development for the years 1962-1970, its antibacterial properties have the following characteristics:
1, the role of Staphylococcus aureus with similar anti-staphylococcal penicillins, are against Staphylococcus aureus β-lactamase the ability of the penicillin-resistant S. aureus effectively. However, if penicillin-resistant S. aureus have been against Staphylococcus aureus, are common to all cephalosporins are resistant.
2, first-generation cephalosporin antibacterial spectrum including group A streptococcus, Streptococcus viridans and Streptococcus pneumoniae, Streptococcus group D of the role of the poor, all cephalosporins (except the microphone outside the cephalosporin sulfur ) of enterococci (eg, fecal streptococci) are invalid.
3, in the generation of antibiotics, antimicrobial spectrum of gram-positive bacteria there are: Staphylococcus epidermidis, Clostridium perfringens, Lee Si te bacteria, Bacillus subtilis, Corynebacterium diphtheriae, etc.
4, the generation of antibiotics against Gram-negative bacteria have a certain role and ampicillin approximation, as described below:
(1) of Neisseria gonorrhoeae and Neisseria meningitidis have good anti-bacterial role, but the former is easy to produce drug-resistant strains.
(2) the part of most Proteus mirabilis strains of the generation of antibiotic-sensitive.
(3) for E. coli, Salmonella, Shigella strains have a stronger role in the majority, but easy to produce drug resistance.
(4) for Klebsiella pneumoniae, cephalosporins have a strong effect (and ampicillin on the bacterium is not valid), but this generation of antibiotics can produce resistant strains.
(5) the generation of antibiotics on Haemophilus influenzae has a certain role. But between this generation of antibiotics and ampicillin on the existence of cross-resistance bacteria, namely, ampicillin-sensitive strains are often also sensitive to the generation of antibiotics, but resistant to ampicillin were also on the generation of antibiotic resistance.
(6) Enterobacter classes are easy on the first-generation cephalosporins.
(7) first-generation cephalosporins invalid for the following microorganisms: Bacillus gas production, indole-positive Proteus, Citrobacter, Pseudomonas, Serratia spp, Bacteroides and other invalid.
5, first-generation cephalosporins against actinomycetes often effective.
first-generation cephalosporins primarily by renal excretion, so there is a higher concentration in urine; in bile concentration is low, does not apply to biliary tract infection; low concentrations in the gut, in addition to oral species, does not apply in intestinal infection; ability to penetrate the blood-brain barrier is weak, does not apply to the central infection.
common with the first-generation cephalosporins, cephalothin, cefotaxime pyridine, cefazolin, cephradine, cephalexin, cefadroxil and so on.
second-generation cephalosporins: The main development for the years 1970-1976, the antibacterial properties of:
1, against Gram-positive bacteria, antimicrobial activity compared with the first-generation cephalosporins, similar or weaker role .
2, Gram-negative bacteria on the antibacterial effect than the first-generation cephalosporins for the superior performance in:
(1) strong performance of anti-enzyme: Escherichia coli, Haemophilus, Neisseria bacteria because microorganisms produce easily understood for the first generation of drug metabolizing enzyme cephalosporin resistance. Second-generation cephalosporin-resistant enzyme strong performance of the bacteria strains resistant to first-generation cephalosporins can be effective.
(2) a wider antibacterial spectrum: in the first-generation cephalosporin antimicrobial spectrum based on second-generation cephalosporin antibacterial spectrum has been expanded to include Citrobacter, indole-positive Proteus part and Enterobacter and so on.
(3) Proteus vulgaris often for the generation of antibiotic resistance. Enterobacter class often produce in a continuous process of medication-resistant strains.
(4) second-generation cephalosporins invalid for the following microorganisms: Streptococcus faecalis, Bacteroides fragilis, Pseudomonas aeruginosa, Acinetobacter, Serratia bacilli.
common with second-generation cephalosporins, cephalosporin Meng and more, Cefuroxime, Cefuroxime Axetil, cefotiam, cefaclor, etc.
third-generation cephalosporins: the generation of antibiotics, anti-bacterial performance characteristics are:
1 ghd gold classic styler, on the role of gram-positive bacteria than first-generation cephalosporins is strong, such as the role of Staphylococcus aureus often low. The role of the streptococcus, cefotaxime strong; but cefoperazone weak. All third-generation cephalosporins against Streptococcus faecalis are not sensitive.
2, the role of Haemophilus, the third-generation cephalosporins and close to the second-generation cephalosporins.
3, E. coli, E. coli, bacteria of various types of variants, and the second-generation cephalosporin-sensitive Gram-negative bacteria have many good effects.
4, the third generation of the antimicrobial spectrum of spore streptozotocin on the basis of the second generation have expanded where to buy christian louboutin shoes, Pseudomonas aeruginosa, Serratia bacteria, Acinetobacter, some anaerobic bacteria, as well as some B. fragilis are There are different degrees of antibacterial activity.
majority of third-generation cephalosporins through the blood-brain barrier, for meningitis caused by susceptible strains.
common with third-generation cephalosporins cefixime, cefotaxime, ceftizoxime, ceftriaxone, cefoperazone, ceftazidime, cefpirome and so on.
fourth-generation cephalosporins: In recent years the development of fourth generation cephalosporins broader antimicrobial spectrum, not only against gram-negative bacteria have a good antibacterial activity, but also resistant Staphylococcus aureus. Therefore, they have broader applicability.
cephalosporin adverse reaction:
(1) Gastrointestinal and flora. Most cephalosporins can cause nausea, vomiting, loss of appetite and other reactions, and inhibit the normal intestinal flora, resulting in a lack of vitamin B and K, and even lead to superinfection, such as pseudomembranous colitis, or other non-susceptible strains of Candida albicans infection.
(2) liver toxicity. Can lead aminotransferase, alkaline phosphatase, elevated serum bilirubin equivalent, but generally not serious.
(3) renal toxicity. Most cephalosporins excreted by the kidneys, can cause blood urea nitrogen (BUN), serum creatinine increased, oliguria, and proteinuria. Cefotaxime pyridine strongest renal damage. Ng aminoglycoside louboutin pumps, a strong diuretic, dextran (injection), etc. can enhance renal toxicity.
(4) hematopoietic toxicity. Can cause red blood cells, leukopenia thrombocytopenia, hemoglobin, and eosinophilia and so on.
(5) coagulopathy. All cephalosporins are inhibiting normal intestinal flora, reduce the production of vitamin K. In the 3-C position with methylthio-tetrazole group of cephalosporins, can compete with vitamin K, thereby preventing glutamate carboxylation, and the resulting thrombin caused the abnormal blood clotting disorders, and some cephalosporin hormone with anti-platelet aggregation, resulting in increased adverse reactions.
(6) inhibition of ethanol metabolism. With methylthio-tetrazole group of cephalosporins inhibit aldehyde dehydrogenase function. If combined with alcohol, can produce disulfide Lun reaction (drunken appearance).
(7) allergic reactions. More common are the skin rashes and drug fever, can still cause asthma, serum sickness-like reaction, angioedema, and anaphylactic shock. Symptoms of anaphylactic shock with penicillin the same shock. Penicillin shock first-aid methods can perform. For cephalosporins allergy history should be banned, there is a history of penicillin allergy should be very careful.
------------------------------------------< br> This article is reproduced From: Flying Fox: cephalosporin class of antibiotics and antibacterial effect of generational
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