The cephalosporins are a class of β-lactam antibiotics

Beta-lactam antibiotic

β-Lactam antibiotics are a broad class of antibiotics, consisting of all antibiotic agents that contains a β-lactam nucleus in its molecular structure. This includes penicillin derivatives , cephalosporins , monobactams, and carbapenems...

 originally derived from Acremonium

Acremonium

Acremonium is a genus of Fungi in the Hypocreaceae family; it was previously known as "Cephalosporium".-Description:Acremonium species are usually slow growing and are initially compact and moist. Acremonium hyphae are fine and hyaline and produce mostly simple phialides. Their conidia are usually...

, which was previously known as "Cephalosporium".

Together with cephamycin

Cephamycin

Cephamycins are a group of beta-lactam antibiotics. They are very similar to cephalosporins, and the cephamycins are sometimes classified as cephalosporins.Like cephalosporins, cephamycins are based upon the cephem nucleus...

s they constitute a subgroup of β-lactam antibiotics called cephem

Cephem

Cephems are a sub-group of beta-lactam antibiotics including cephalosporins and cephamycins....

s.

Medical use

Cephalosporins are indicated for the prophylaxis and treatment of infections caused by bacteria

Bacteria

Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...

 susceptible to this particular form of antibiotic. First-generation cephalosporins are active predominantly against Gram-positive

Gram-positive

Gram-positive bacteria are those that are stained dark blue or violet by Gram staining. This is in contrast to Gram-negative bacteria, which cannot retain the crystal violet stain, instead taking up the counterstain and appearing red or pink...

 bacteria, and successive generations have increased activity against Gram-negative

Gram-negative

Gram-negative bacteria are bacteria that do not retain crystal violet dye in the Gram staining protocol. In a Gram stain test, a counterstain is added after the crystal violet, coloring all Gram-negative bacteria with a red or pink color...

 bacteria (albeit often with reduced activity against Gram-positive organisms).

Adverse effects

Common adverse drug reaction

Adverse drug reaction

An adverse drug reaction is an expression that describes harm associated with the use of given medications at a normal dosage. ADRs may occur following a single dose or prolonged administration of a drug or result from the combination of two or more drugs...

s (ADRs) (≥1% of patients) associated with the cephalosporin therapy include: diarrhea, nausea, rash, electrolyte disturbances, and/or pain and inflammation at injection site. Infrequent ADRs (0.1–1% of patients) include: vomiting, headache, dizziness, oral and vaginal candidiasis

Candidiasis

Thrush redirects here. For the hoof infection see Thrush .Candidiasis or thrush is a fungal infection of any of the Candida species , of which Candida albicans is the most common...

, pseudomembranous colitis

Pseudomembranous colitis

Pseudomembranous colitis, a cause of antibiotic-associated diarrhea , is an infection of the colon. It is often, but not always, caused by the bacterium Clostridium difficile. Because of this, the informal name C. difficile colitis is also commonly used. The illness is characterized by...

, superinfection

Superinfection

In virology, superinfection is the process by which a cell, that has previously been infected by one virus, gets coinfected with a different strain of the virus, or another virus at a later point in time. Viral superinfections of serious conditions can lead to resistant strains of the virus, which...

, eosinophilia

Eosinophilia

Eosinophilia is a condition in which the eosinophil count in the peripheral blood exceeds 0.45×109/L . A marked increase in non-blood tissue eosinophil count noticed upon histopathologic examination is diagnostic for tissue eosinophilia. Several causes are known, with the most common being...

, and/or fever.

The commonly quoted figure of 10% of patients with allergic hypersensitivity to penicillin

Penicillin

Penicillin is a group of antibiotics derived from Penicillium fungi. They include penicillin G, procaine penicillin, benzathine penicillin, and penicillin V....

s and/or carbapenem

Carbapenem

Carbapenems are a class of β-lactam antibiotics with a broad spectrum of antibacterial activity. They have a structure that renders them highly resistant to most β-lactamases...

s also having cross-reactivity with cephalosporins originated from a 1975 study looking at the original cephalosporins, and subsequent "safety first" policy meant this was widely quoted and assumed to apply to all members of the group. Hence it was commonly stated that they are contraindicated in patients with a history of severe, immediate allergic reactions (urticaria

Urticaria

Urticaria is a kind of skin rash notable for pale red, raised, itchy bumps. Hives is frequently caused by allergic reactions; however, there are many non-allergic causes...

, anaphylaxis

Anaphylaxis

Anaphylaxis is defined as "a serious allergic reaction that is rapid in onset and may cause death". It typically results in a number of symptoms including throat swelling, an itchy rash, and low blood pressure...

, interstitial nephritis

Interstitial nephritis

Interstitial nephritis is a form of nephritis affecting the interstitium of the kidneys surrounding the tubules...

, etc.) to penicillins, carbapenems or cephalosporins. This, however, should be viewed in the light of recent epidemiological work suggesting that, for many second-generation (or later) cephalosporins, the cross-reactivity rate with penicillin is much lower, having no significantly increased risk of reactivity in the studies examined. The British National Formulary

British National Formulary

The British National Formulary is a medical and pharmaceutical reference book that contains a wide spectrum of information and advice on prescribing and pharmacology, along with specific facts and details about all medicines available on the National Health Service , including indication,...

 previously issued blanket warnings of 10% cross reactivity, but, since the September 2008 edition, suggests in the absence of suitable alternatives that oral cefixime or cefuroxime and injectable cefotaxime, ceftazidine, and ceftriaxone can be used with caution, but to avoid cefaclor, cefadrocil, cefalexin, and cefradine.

Several cephalosporins are associated with hypoprothrombinemia

Hypoprothrombinemia

Hypoprothrombinemia is a blood disorder in which a deficiency of prothrombin results in impaired blood clotting, leading to an increased physiological risk for bleeding, especially in the gastrointestinal system, cranial vault, and superficial integumentary system.-Causes:Hypoprothrombinemia can...

 and a disulfiram

Disulfiram

Disulfiram is a drug discovered in the 1920s and used to support the treatment of chronic alcoholism by producing an acute sensitivity to alcohol. Trade names for disulfiram in different countries are Antabuse and Antabus manufactured by Odyssey Pharmaceuticals...

-like reaction with ethanol. These include latamoxef

Latamoxef

Latamoxef is an oxacephem antibiotic usually grouped with the cephalosporins. In oxacephems such as latamoxef, the sulfur atom of the cephalosporin core is replaced with an oxygen atom....

, cefmenoxime

Cefmenoxime

Cefmenoxime is a third-generation cephalosporin antibiotic....

, moxalactam, cefoperazone

Cefoperazone

Cefoperazone is a third generation cephalosporin antibiotic, marketed by Pfizer under the name Cefobid, and also marked by pharco B international under the name of Cefazoneand also marketed by "sigmatec " under the name " cefoperazone"...

, cefamandole

Cefamandole

Cefamandole is a second-generation broad-spectrum cephalosporin antibiotic. The clinically used form of cefamandole is the formate ester cefamandole nafate, a prodrug which is administered parenterally....

, cefmetazole

Cefmetazole

Cefmetazole is a cephalosporin antibiotic, usually grouped with the second-generation cephalosporins.-Adverse effects:The chemical structure of cefmetazole, like that of several other cephalosporins, contains an N-methylthiotetrazole side chain...

, and cefotetan

Cefotetan

Cefotetan is an injectable antibiotic of the cephamycin type for prophylaxis and treatment of bacterial infections. It is often grouped together with second-generation cephalosporins and has a similar antibacterial spectrum, but with additional anti-anaerobe coverage.Cefotetan was developed by...

. This is thought to be due to the N-methylthiotetrazole (NMTT) side-chain of these cephalosporins, which blocks the enzyme vitamin K epoxide reductase

Vitamin K epoxide reductase

Vitamin K epoxide reductase is an enzyme that reduces vitamin K after it has been oxidised in the carboxylation of glutamic acid. Its C1 subunit is the target of anticoagulant warfarin.- See also :* Oxidoreductase...

 (likely causing hypothrombinemia) and aldehyde dehydrogenase

Aldehyde dehydrogenase

Aldehyde dehydrogenases are a group of enzymes that catalyse the oxidation of aldehydes.- Function :Aldehyde dehydrogenase is a polymorphic enzyme responsible for the oxidation of aldehydes to carboxylic acids, which leave the liver and are metabolized by the body’s muscle and heart...

 (causing alcohol intolerance).

Mechanism of action

Cephalosporins are bactericidal and have the same mode of action as other beta-lactam antibiotic

Beta-lactam antibiotic

β-Lactam antibiotics are a broad class of antibiotics, consisting of all antibiotic agents that contains a β-lactam nucleus in its molecular structure. This includes penicillin derivatives , cephalosporins , monobactams, and carbapenems...

s (such as penicillin

Penicillin

Penicillin is a group of antibiotics derived from Penicillium fungi. They include penicillin G, procaine penicillin, benzathine penicillin, and penicillin V....

s) but are less susceptible to penicillinases

Beta-lactamase

Beta-lactamases are enzymes produced by some bacteria and are responsible for their resistance to beta-lactam antibiotics like penicillins, cephamycins, and carbapenems . These antibiotics have a common element in their molecular structure: a four-atom ring known as a beta-lactam...

. Cephalosporins disrupt the synthesis of the peptidoglycan

Peptidoglycan

Peptidoglycan, also known as murein, is a polymer consisting of sugars and amino acids that forms a mesh-like layer outside the plasma membrane of bacteria , forming the cell wall. The sugar component consists of alternating residues of β- linked N-acetylglucosamine and N-acetylmuramic acid...

 layer of bacterial cell wall

Cell wall

The cell wall is the tough, usually flexible but sometimes fairly rigid layer that surrounds some types of cells. It is located outside the cell membrane and provides these cells with structural support and protection, and also acts as a filtering mechanism. A major function of the cell wall is to...

s. The peptidoglycan layer is important for cell wall structural integrity. The final transpeptidation step in the synthesis of the peptidoglycan is facilitated by transpeptidase

Transpeptidase

A transpeptidase is a bacterial enzyme that cross-links the peptidoglycan chains to form rigid cell walls. This enzyme is also known by several other names including DD-peptidase, DD-transpeptidase, D-alanyl-D-alanine carboxypeptidase and serine-type D-Ala-D-Ala carboxypeptidase...

s known as penicillin-binding proteins (PBPs). PBPs bind to the D-Ala-D-Ala at the end of muropeptides (peptidoglycan precursors) to crosslink the peptidoglycan. Beta-lactam antibiotic

Beta-lactam antibiotic

β-Lactam antibiotics are a broad class of antibiotics, consisting of all antibiotic agents that contains a β-lactam nucleus in its molecular structure. This includes penicillin derivatives , cephalosporins , monobactams, and carbapenems...

s mimic the D-Ala-D-Ala site, thereby competitively inhibiting PBP crosslinking of peptidoglycan.

Classification

The cephalosporin nucleus can be modified to gain different properties. Cephalosporins are sometimes grouped into "generations" by their antimicrobial

Antimicrobial

An anti-microbial is a substance that kills or inhibits the growth of microorganisms such as bacteria, fungi, or protozoans. Antimicrobial drugs either kill microbes or prevent the growth of microbes...

 properties. The first cephalosporins were designated first-generation cephalosporins, whereas, later, more extended-spectrum

Spectrum

A spectrum is a condition that is not limited to a specific set of values but can vary infinitely within a continuum. The word saw its first scientific use within the field of optics to describe the rainbow of colors in visible light when separated using a prism; it has since been applied by...

 cephalosporins were classified as second-generation cephalosporins. Each newer generation of cephalosporins has significantly greater Gram-negative

Gram-negative

Gram-negative bacteria are bacteria that do not retain crystal violet dye in the Gram staining protocol. In a Gram stain test, a counterstain is added after the crystal violet, coloring all Gram-negative bacteria with a red or pink color...

 antimicrobial properties than the preceding generation, in most cases with decreased activity against Gram-positive

Gram-positive

Gram-positive bacteria are those that are stained dark blue or violet by Gram staining. This is in contrast to Gram-negative bacteria, which cannot retain the crystal violet stain, instead taking up the counterstain and appearing red or pink...

 organisms. Fourth-generation cephalosporins, however, have true broad-spectrum activity.

The classification of cephalosporins into "generations" is commonly practised, although the exact categorization of cephalosporins is often imprecise. For example, the fourth generation of cephalosporins is not recognized as such, in Japan. In Japan, cefaclor is classed as a first-generation cephalosporin, even though in the United States it is a second-generation one; and cefbuperazone, cefminox, and cefotetan are classed as second-generation cephalosporins. Cefmetazole and cefoxitin are classed as third-generation cephems. Flomoxef, latamoxef are in a new class called oxacephem

Oxacephem

An oxacephem is a molecule similar to a cephem, but with oxygen substituted for the sulfur. They are synthetically made compounds and have not been discovered in nature.An example is moxalactam.Another example is flomoxef....

s.

Most first-generation cephalosporins were originally spelled "ceph-" in English-speaking countries. This continues to be the preferred spelling in the United States and Australia, while European countries (including the United Kingdom) have adopted the International Nonproprietary Name

International Nonproprietary Name

An International Nonproprietary Name is the official nonproprietary or generic name given to a pharmaceutical substance, as designated by the World Health Organization...

s, which are always spelled "cef-". Newer first-generation cephalosporins and all cephalosporins of later generations are spelled "cef-", even in the United States.

Some state that, although cephalosporins can be divided into five or even six generations, the usefulness of this organization system is of limited clinical relevance.

Fourth-generation Cephalosporins as of March, 2007 were considered to be "a class of highly potent antibiotics that are among medicine's last defenses against several serious human infections" according to the Washington Post.

#	Members	Description
1	Cefacetrile Cefacetrile Cefacetrile is a broad-spectrum first generation cephalosporin antibiotic effective in Gram-positive and Gram-negative bacterial infections. It is a bacteriostatic antibiotic. Cefacetrile is marketed under the trade names Celospor, Celtol, and Cristacef....  (cephacetrile), Cefadroxil Cefadroxil Cefadroxil is a broad-spectrum antibiotic of the cephalosporin type, effective in Gram-positive and Gram-negative bacterial infections. It is a bactericidal antibiotic.- General use :...  (cefadroxyl; Duricef), Cephalexin (cephalexin; Keflex), Cefaloglycin (cephaloglycin), Cefalonium Cefalonium Cefalonium is a first-generation cephalosporin antibiotic....  (cephalonium), Cefaloridine Cefaloridine Cephaloridine is a first generation semisynthetic derivative of cephalosporin C. It is unique among cephalosporins in that it exists as a zwitterion.-History:...  (cephaloradine), Cefalotin Cefalotin Cefalotin or cephalothin is a first-generation cephalosporin antibiotic. It was the first cephalosporin marketed and continues to be widely used. It is an intravenously administered agent with a similar antimicrobial spectrum to cefazolin and the oral agent cefalexin. Cefalotin sodium is...  (cephalothin; Keflin), Cefapirin Cefapirin Cefapirin is an injectable, first-generation cephalosporin antibiotic. It is marketed under the trade name Cefadyl...  (cephapirin; Cefadryl), Cefatrizine Cefatrizine Cefatrizine is a broad-spectrum cephalosporin antibiotic.... , Cefazaflur Cefazaflur Cefazaflur is a first-generation cephalosporin antibiotic.... , Cefazedone Cefazedone Cefazedone is a cephalosporin antibiotic.-External links:*... , Cefazolin Cefazolin Cefazolin , also known as cefazoline or cephazolin, is a first-generation cephalosporin antibiotic.The drug is usually administrated by either intramuscular injection or intravenous infusion .-Indications:Cefazolin is mainly used to treat bacterial infections of the skin...  (cephazolin; Ancef, Kefzol), Cefradine (cephradine; Velosef), Cefroxadine Cefroxadine Cefroxadine is a cephalosporin antibiotic. It is structurally related to cefalexin, and both drugs share a similar spectrum of activity.It is available in Italy.... , Ceftezole Ceftezole Ceftezole is a cephalosporin antibiotic.... .	Gram-positive: Activity against penicillinase-producing, methicillin-susceptible staphylococci Staphylococcus Staphylococcus is a genus of Gram-positive bacteria. Under the microscope they appear round , and form in grape-like clusters....  and streptococci Streptococcus Streptococcus is a genus of spherical Gram-positive bacteria belonging to the phylum Firmicutes and the lactic acid bacteria group. Cellular division occurs along a single axis in these bacteria, and thus they grow in chains or pairs, hence the name — from Greek στρεπτος streptos, meaning...  (though they are not the drugs of choice for such infections). No activity against methicillin-resistant staphylococci or enterococci Enterococcus Enterococcus is a genus of lactic acid bacteria of the phylum Firmicutes. Enterococci are Gram-positive cocci that often occur in pairs or short chains, and are difficult to distinguish from streptococci on physical characteristics alone. Two species are common commensal organisms in the... . Gram-negative: Activity against Proteus mirabilis Proteus (bacterium) Proteus is a genus of Gram-negative Proteobacteria.-Clinical significance:Three species—P. vulgaris, P. mirabilis, and P. penneri—are opportunistic human pathogens. Proteus includes pathogens responsible for many human urinary tract infections. P. mirabilis causes wound and urinary... , some Escherichia coli Escherichia coli Escherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls... , and Klebsiella pneumoniae Klebsiella pneumoniae Klebsiella pneumoniae is a Gram-negative, non-motile, encapsulated, lactose fermenting, facultative anaerobic, rod shaped bacterium found in the normal flora of the mouth, skin, and intestines.... ("PEcK"), but have no activity against Bacteroides fragilis Bacteroides fragilis Bacteroides fragilis is a Gram-negative bacillus bacterium species, and an obligate anaerobe of the gut.B. fragilis group is the most commonly isolated bacteriodaceae in anaerobic infections especially those that originate from the gastrointestinal flora. B. fragilis is the most prevalent organism... , Pseudomonas Pseudomonas Pseudomonas is a genus of gammaproteobacteria, belonging to the family Pseudomonadaceae containing 191 validly described species.Recently, 16S rRNA sequence analysis has redefined the taxonomy of many bacterial species. As a result, the genus Pseudomonas includes strains formerly classified in the... , Acinetobacter Acinetobacter Acinetobacter [asz−in−ée−toe–back−ter] is a genus of Gram-negative bacteria belonging to the Gammaproteobacteria. Acinetobacter species are non-motile and oxidase-negative, and occur in pairs under magnification.... , Enterobacter Enterobacter Enterobacter is a genus of common Gram-negative, facultatively-anaerobic, rod-shaped bacteria of the family Enterobacteriaceae. Several strains of the these bacteria are pathogenic and cause opportunistic infections in immunocompromised hosts and in those who are on mechanical ventilation... , indole-positive Proteus Proteus (bacterium) Proteus is a genus of Gram-negative Proteobacteria.-Clinical significance:Three species—P. vulgaris, P. mirabilis, and P. penneri—are opportunistic human pathogens. Proteus includes pathogens responsible for many human urinary tract infections. P. mirabilis causes wound and urinary... , or Serratia Serratia Serratia is a genus of Gram-negative, facultatively anaerobic, rod-shaped bacteria of the Enterobacteriaceae family. The most common species in the genus, S. marcescens, is normally the only pathogen and usually causes nosocomial infections. However, rare strains of S. plymuthica, S. liquefaciens,... .
2	Cefaclor Cefaclor Cefaclor, also known as cefachlor or cefaclorum , is a second-generation cephalosporin antibiotic used to treat certain infections caused by bacteria such as pneumonia and ear, lung, skin, throat, and urinary tract infections.- Indications:Cefaclor belongs to the family of antibiotics known as the...   (Ceclor, Distaclor, Keflor, Raniclor), Cefonicid Cefonicid Cefonicide is a cephalosporin antibiotic.It has a density of 1.92g/cm3....  (Monocid), Cefprozil Cefprozil Cefprozil, sometimes spelled cefproxil and marketed under the trade name Cefzil, is a second-generation cephalosporin type antibiotic. In Europe it is marketed using the trade names Procef and Cronocef. It can be used to treat bronchitis, ear infections, skin infections, and other bacterial...  (cefproxil; Cefzil), Cefuroxime Cefuroxime Cefuroxime is a second-generation cephalosporin antibiotic that has been widely available in the USA as Ceftin since 1977. GlaxoSmithKline sells the antibiotic in the United Kingdom under the name Zinnat.-Indications:As for the other cephalosporins, although as a...  (Zefu, Zinnat, Zinacef, Ceftin, Biofuroksym, Xorimax), Cefuzonam Cefuzonam Cefuzonam is a second-generation cephalosporin antibiotic.... . Second generation cephalosporins with antianaerobe activity: Cefmetazole Cefmetazole Cefmetazole is a cephalosporin antibiotic, usually grouped with the second-generation cephalosporins.-Adverse effects:The chemical structure of cefmetazole, like that of several other cephalosporins, contains an N-methylthiotetrazole side chain... , Cefotetan Cefotetan Cefotetan is an injectable antibiotic of the cephamycin type for prophylaxis and treatment of bacterial infections. It is often grouped together with second-generation cephalosporins and has a similar antibacterial spectrum, but with additional anti-anaerobe coverage.Cefotetan was developed by... , Cefoxitin Cefoxitin Cefoxitin is a cephamycin antibiotic developed by Merck & Co., Inc., often grouped with the second−generation cephalosporins. It is sold under the brand name Mefoxin.- Microbiology :... . The following cephems are also sometimes grouped with second-generation cephalosporins: Carbacephem Carbacephem A carbacephem is a type of synthetically made antibiotic, based on the structure of cephalosporin, a cephem. Carbacephems are similar to cephems but with a carbon substituted for the sulfur.... s: loracarbef Loracarbef Loracarbef is an antibiotic. Its use was discontinued in 2006. It is a carbacephem, but it is sometimes grouped together with the second-generation cephalosporin antibiotics. It was marketed under the trade name Lorabid....  (Lorabid); Cephamycin Cephamycin Cephamycins are a group of beta-lactam antibiotics. They are very similar to cephalosporins, and the cephamycins are sometimes classified as cephalosporins.Like cephalosporins, cephamycins are based upon the cephem nucleus... s: cefbuperazone Cefbuperazone Cefbuperazone is a second-generation cephalosporin antibiotic.... , cefmetazole Cefmetazole Cefmetazole is a cephalosporin antibiotic, usually grouped with the second-generation cephalosporins.-Adverse effects:The chemical structure of cefmetazole, like that of several other cephalosporins, contains an N-methylthiotetrazole side chain...  (Zefazone), cefminox Cefminox Cefminox is a second-generation cephalosporin antibiotic.... , cefotetan Cefotetan Cefotetan is an injectable antibiotic of the cephamycin type for prophylaxis and treatment of bacterial infections. It is often grouped together with second-generation cephalosporins and has a similar antibacterial spectrum, but with additional anti-anaerobe coverage.Cefotetan was developed by...  (Cefotan), cefoxitin Cefoxitin Cefoxitin is a cephamycin antibiotic developed by Merck & Co., Inc., often grouped with the second−generation cephalosporins. It is sold under the brand name Mefoxin.- Microbiology :...  (Mefoxin).	Gram-positive: Less than first-generation. Gram-negative: Greater than first-generation: HEN (Haemophilus influenzae Haemophilus influenzae Haemophilus influenzae, formerly called Pfeiffer's bacillus or Bacillus influenzae, Gram-negative, rod-shaped bacterium first described in 1892 by Richard Pfeiffer during an influenza pandemic. A member of the Pasteurellaceae family, it is generally aerobic, but can grow as a facultative anaerobe. H... , Enterobacter aerogenes Enterobacter aerogenes Enterobacter aerogenes is a Gram-negative, oxidase negative, catalase positive, citrate positive, indole negative, rod-shaped bacterium.... and some Neisseria Neisseria The Neisseria is a large genus of commensal bacteria that colonize the mucosal surfaces of many animals. Of the 11 species that colonize humans, only two are pathogens. N. meningitidis and N. gonorrhoeae often cause asymptomatic infections, a commensal-like behavior... + the PEcK described above.
3	Cefcapene Cefcapene Cefcapene is a third-generation cephalosporin antibiotic.... , Cefdaloxime Cefdaloxime Cefdaloxime is a third-generation cephalosporin antibiotic.... , Cefdinir Cefdinir Cefdinir is a semi-synthetic, broad-spectrum antibiotic in the third generation of the cephalosporin class, proven effective for common bacterial infections of the ear, sinus, throat, and skin. It was approved by the U.S...  (Zinir, Omnicef, Kefnir), Cefditoren Cefditoren Cefditoren is a third-generation cephalosporin antibiotic for oral use. It is commonly marketed under the trade name Spectracef by Cornerstone BioPharma.Cefditoren is also marketed under the name Meiact.-Indications:... , Cefetamet Cefetamet Cefetamet is a cephalosporin antibiotic.... , Cefixime Cefixime Cefixime is an oral third generation cephalosporin antibiotic. Cefixime is a cephalosporin antibiotic used to treat infections caused by bacteria such as pneumonia; bronchitis; gonorrhea; and ear, lung, throat, and urinary tract infections...  (Zifi, Suprax), Cefmenoxime Cefmenoxime Cefmenoxime is a third-generation cephalosporin antibiotic.... , Cefodizime Cefodizime Cefodizime is a cephalosporin.... , Cefotaxime Cefotaxime Cefotaxime is a third-generation cephalosporin antibiotic. Like other third-generation cephalosporins, it has broad spectrum activity against Gram positive and Gram negative bacteria...  (Claforan), Cefovecin Cefovecin Cefovecin is an antibiotic of the cephalosporin class, licensed for the treatment of skin infections in cats and dogs. It is marketed by Pfizer under the trade name Convenia.-Approval and usage:...  (Convenia), Cefpimizole Cefpimizole Cefpimizole is a third-generation cephalosporin antibiotic.... , Cefpodoxime Cefpodoxime Cefpodoxime is an oral third generation cephalosporin antibiotic. It is marketed as the prodrug cefpodoxime proxetil by Pharmacia & Upjohn under the trade name Vantin. It is active against most Gram positive and Gram negative organisms. Notable exceptions include Pseudomonas aeruginosa,...  (Vantin, PECEF), Cefteram Cefteram Cefteram is a third-generation cephalosporin antibiotic.... , Ceftibuten Ceftibuten Ceftibuten is a third-generation cephalosporin antibiotic. It is an orally-administered agent, with 2 dosage forms, capsule or oral suspension. It is marketed by Pernix Therapeutics under the trade name Cedax....  (Cedax), Ceftiofur Ceftiofur Ceftiofur is an antibiotic of the cephalosporin type , licensed for use in veterinary medicine. It was first described in 1987. It is marketed by pharmaceutical company Pfizer as Excede.... , Ceftiolene Ceftiolene Ceftiolene is a third-generation cephalosporin antibiotic.... , Ceftizoxime Ceftizoxime Ceftizoxime is a parenteral third-generation cephalosporin.Unlike other 3rd generation cephalosporins , in ceftizoxime the whole C-3 side chain has been removed to prevent deactivation by hydrolytic enzymes ....  (Cefizox), Ceftriaxone Ceftriaxone Ceftriaxone is a third-generation cephalosporin antibiotic. Like other third-generation cephalosporins, it has broad spectrum activity against Gram-positive and Gram-negative bacteria. In most cases, it is considered to be equivalent to cefotaxime in terms of safety and efficacy...  (Rocephin). Third-generation cephalosporins with antipseudomonal activity: Cefoperazone Cefoperazone Cefoperazone is a third generation cephalosporin antibiotic, marketed by Pfizer under the name Cefobid, and also marked by pharco B international under the name of Cefazoneand also marketed by "sigmatec " under the name " cefoperazone"...  (Cefobid), Ceftazidime Ceftazidime Ceftazidime is a third-generation cephalosporin antibiotic. Like other third-generation cephalosporins, it has broad spectrum activity against Gram-positive and Gram-negative bacteria. Unlike most third-generation agents, it is active against Pseudomonas aeruginosa, however it has weaker activity...  (Fortum, Fortaz). The following cephems are also sometimes grouped with third-generation cephalosporins: Oxacephem Oxacephem An oxacephem is a molecule similar to a cephem, but with oxygen substituted for the sulfur. They are synthetically made compounds and have not been discovered in nature.An example is moxalactam.Another example is flomoxef.... s: latamoxef Latamoxef Latamoxef is an oxacephem antibiotic usually grouped with the cephalosporins. In oxacephems such as latamoxef, the sulfur atom of the cephalosporin core is replaced with an oxygen atom....  (moxalactam).	Gram-positive: Some members of this group (in particular, those available in an oral formulation, and those with anti-pseudomonal activity) have decreased activity against Gram-positive organisms. Gram-negative: Third-generation cephalosporins have a broad spectrum of activity and further increased activity against Gram-negative organisms. They may be particularly useful in treating hospital-acquired infection Nosocomial infection A nosocomial infection , also known as a hospital-acquired infection or HAI, is an infection whose development is favoured by a hospital environment, such as one acquired by a patient during a hospital visit or one developing among hospital staff... s, although increasing levels of extended-spectrum beta-lactamases are reducing the clinical utility of this class of antibiotics. They are also able to penetrate the CNS Central nervous system The central nervous system is the part of the nervous system that integrates the information that it receives from, and coordinates the activity of, all parts of the bodies of bilaterian animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish... , making them useful against meningitis caused by pneumococci, meningococci, H. influenzae, and susceptible E. coli, Klebsiella, and penicillin-resistant N. gonorrhoeae. Since 2007, third-generation cephalosporins (ceftriaxone or cefixime) have been the only recommended treatment for gonorrhea in the United States.
4	Cefclidine Cefclidine Cefclidine is a cephalosporin.... , Cefepime Cefepime Cefepime is a fourth-generation cephalosporin antibiotic developed in 1994. Cefepime has an extended spectrum of activity against Gram-positive and Gram-negative bacteria, with greater activity against both Gram-negative and Gram-positive organisms than third-generation agents...  (Maxipime), Cefluprenam Cefluprenam Cefluprenam is a cephalosporin.... , Cefoselis Cefoselis Cefoselis is a cephalosporin.... , Cefozopran Cefozopran Cefozopran is a fourth-generation cephalosporin.... , Cefpirome Cefpirome Cefpirome is a fourth-generation cephalosporin. Trade names include Cefrom, Keiten, Broact, Cefir. Cefpirome is considered highly active against Gram-negative bacteria, including Pseudomonas aeruginosa, and Gram-positive bacteria....  (Cefrom), Cefquinome. The following cephems are also sometimes grouped with fourth-generation cephalosporins: Oxacephem Oxacephem An oxacephem is a molecule similar to a cephem, but with oxygen substituted for the sulfur. They are synthetically made compounds and have not been discovered in nature.An example is moxalactam.Another example is flomoxef.... s: flomoxef Flomoxef Flomoxef is an oxacephem antibiotic.It has been identified as second-generation and fourth generation....	Gram-positive: They are extended-spectrum agents with similar activity against Gram-positive organisms as first-generation cephalosporins. Gram-negative: Fourth-generation cephalosporins are zwitterion Zwitterion In chemistry, a zwitterion is a neutral molecule with a positive and a negative electrical charge at different locations within that molecule. Zwitterions are sometimes also called inner salts.-Examples:... s that can penetrate the outer membrane of Gram-negative bacteria. They also have a greater resistance to beta-lactamases than the third-generation cephalosporins. Many can cross the blood-brain barrier Blood-brain barrier The blood–brain barrier is a separation of circulating blood and the brain extracellular fluid in the central nervous system . It occurs along all capillaries and consists of tight junctions around the capillaries that do not exist in normal circulation. Endothelial cells restrict the diffusion...  and are effective in meningitis Meningitis Meningitis is inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges. The inflammation may be caused by infection with viruses, bacteria, or other microorganisms, and less commonly by certain drugs... . They are also used against Pseudomonas aeruginosa Pseudomonas aeruginosa Pseudomonas aeruginosa is a common bacterium that can cause disease in animals, including humans. It is found in soil, water, skin flora, and most man-made environments throughout the world. It thrives not only in normal atmospheres, but also in hypoxic atmospheres, and has, thus, colonized many... .
5	Ceftobiprole Ceftobiprole Ceftobiprole is a 4th generation cephalosporin antibiotic with activity against methicillin-resistant Staphylococcus aureus, penicillin-resistant Streptococcus pneumoniae, Pseudomonas aeruginosa, and Enterococci. It was discovered by Basilea Pharmaceutica and was developed by Johnson & Johnson... , Ceftaroline Ceftaroline Ceftaroline fosamil is an advanced-generation cephalosporin antibiotic. It is active against methicillin-resistant Staphylococcus aureus and Gram-positive bacteria. It retains the activity of later-generation cephalosporins having broad-spectrum activity against Gram-negative bacteria...	Ceftobiprole Ceftobiprole Ceftobiprole is a 4th generation cephalosporin antibiotic with activity against methicillin-resistant Staphylococcus aureus, penicillin-resistant Streptococcus pneumoniae, Pseudomonas aeruginosa, and Enterococci. It was discovered by Basilea Pharmaceutica and was developed by Johnson & Johnson...  has been described as "fifth-generation" cephalosporin, though acceptance for this terminology is not universal. Ceftobiprole (and the soluble prodrug medocaril) are on the FDA fast-track. Ceftobiprole has powerful antipseudomonal characteristics and appears to be less susceptible to development of resistance. Ceftaroline Ceftaroline Ceftaroline fosamil is an advanced-generation cephalosporin antibiotic. It is active against methicillin-resistant Staphylococcus aureus and Gram-positive bacteria. It retains the activity of later-generation cephalosporins having broad-spectrum activity against Gram-negative bacteria...  has also been described as "fifth-generation" cephalosporin.

Other

These cephems have progressed far enough to be named, but have not been assigned to a particular generation: Cefaloram, Cefaparole, Cefcanel, Cefedrolor, Cefempidone, Cefetrizole, Cefivitril, Cefmatilen

Cefmatilen

Cefmatilen is an orally-active cephalosporin antibiotic. It was developed in Japan and first described in 1992.In vitro, cefmatilen is highly active against a variety of Gram-positive and Gram-negative bacteria, including Streptococcus pyogenes and Neisseria gonorrhoeae....

, Cefmepidium, Cefoxazole, Cefrotil, Cefsumide, Ceftioxide, Cefuracetime.

History

Cephalosporin compounds were first isolated from cultures of Cephalosporium acremonium from a sewer in Sardinia

Sardinia

Sardinia is the second-largest island in the Mediterranean Sea . It is an autonomous region of Italy, and the nearest land masses are the French island of Corsica, the Italian Peninsula, Sicily, Tunisia and the Spanish Balearic Islands.The name Sardinia is from the pre-Roman noun *sard[],...

 in 1948 by Italian scientist Giuseppe Brotzu. He noticed that these cultures produced substances that were effective against Salmonella typhi, the cause of typhoid fever

Typhoid fever

Typhoid fever, also known as Typhoid, is a common worldwide bacterial disease, transmitted by the ingestion of food or water contaminated with the feces of an infected person, which contain the bacterium Salmonella enterica, serovar Typhi...

, which hadbeta-lactamase

Beta-lactamase

Beta-lactamases are enzymes produced by some bacteria and are responsible for their resistance to beta-lactam antibiotics like penicillins, cephamycins, and carbapenems . These antibiotics have a common element in their molecular structure: a four-atom ring known as a beta-lactam...

. Guy Newton

Guy Newton

Guy Geoffrey Frederick Newton was a British rower and biochemist. He was the co-discoverer of cephalosporin C.Newton was born in St. Ives, Cambridgeshire, the son of Bernard Newton a gentleman farmer of Fairfield Bury, St Ives and his wife Antoinette Gerard. He was educated at Oundle School and...

 and Edward Abraham

Edward Abraham

Edward Penley Abraham, CBE, FRS was an English biochemist instrumental in the development of penicillin.-Life:...

 at the Sir William Dunn School of Pathology

Sir William Dunn School of Pathology

The Sir William Dunn School of Pathology is a Department within the University of Oxford . Its research programme includes the cellular and molecular biology of pathogens, the immune response, cancer and cardiovascular disease...

 at the University of Oxford

University of Oxford

The University of Oxford is a university located in Oxford, United Kingdom. It is the second-oldest surviving university in the world and the oldest in the English-speaking world. Although its exact date of foundation is unclear, there is evidence of teaching as far back as 1096...

 isolated cephalosporin C

Cephalosporin C

Cephalosporin C is an antibiotic of the cephalosporin class. It was isolated from fungi of the genus Acremonium and first characterized in 1961. Although not a very active antibiotic itself, synthetic analogs of cephalosporin C, such as cefalotin, became some of the first marketed cephalosporin...

. The cephalosporin nucleus, 7-aminocephalosporanic acid

7-ACA

7-ACA is the core chemical structure for the synthesis of cephalosporin antibiotics and intermediates. It can be obtained by chemoenzymatic hydrolysis of cephalosporin C....

 (7-ACA), was derived from cephalosporin C and proved to be analogous to the penicillin

Penicillin

Penicillin is a group of antibiotics derived from Penicillium fungi. They include penicillin G, procaine penicillin, benzathine penicillin, and penicillin V....

 nucleus 6-aminopenicillanic acid

6-APA

6-APA is the chemical compound -6-aminopenicillanic acid.-Use:6-APA is the core of penicillins. It is obtained from the fermentation brew of the Penicillium mold and used as the main starting block for the preparation of numerous semisynthetic penicillins.-Manufacture:This useful compound is made...

 (6-APA), but it was not sufficiently potent for clinical use. Modification of the 7-ACA side-chains resulted in the development of useful antibiotic agents, and the first agent cefalotin

Cefalotin

Cefalotin or cephalothin is a first-generation cephalosporin antibiotic. It was the first cephalosporin marketed and continues to be widely used. It is an intravenously administered agent with a similar antimicrobial spectrum to cefazolin and the oral agent cefalexin. Cefalotin sodium is...

 (cephalothin) was launched by Eli Lilly and Company

Eli Lilly and Company

Eli Lilly and Company is a global pharmaceutical company. Eli Lilly's global headquarters is located in Indianapolis, Indiana, in the United States...

in 1964.