Antibiotics Introduction

of 6
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Related Documents
  Antibiotics IntroductionAntibiotics, also known as antibacterials, are types of medications that destroy or slow downthe growth of bacteria. The Greek word anti   means against , and the Greek word bios  means life (bacteria are life forms). Antibiotics are among the most frequently prescribed medications in modern medicine.Antibiotics cure disease by killing or injuring bacteria. The first antibiotic was penicillin, discoveredaccidentally from a mold culture. Today, over 100 different antibiotics are available to cure minor, as wellas lifethreatening infections.Although antibiotics are useful in a wide variety of infections, it is important to reali!e thatantibiotics only treat bacterial  infections. Antibiotics are useless against viral infections for e#ample, thecommon cold$ and fungal infections such as ringworm$. %our doctor can best determine if an antibiotic isright for your condition. The first antibiotic was penicillin . &uch penicillinrelated antibiotics as ampicillin, amo#icillinand ben!yl penicilllin are widely used today to treat a variety of infections  these antibiotics have beenaround for a long time. Types of Antibiotics Although there are well over 100 antibiotics, the majority come from only a few types of drugs. Theseare the main classes of antibiotics. ã 'enicillins such as penicillin and amo#icillin ã (ephalosporins such as cephale#in )efle#$*acrolides such as erythromycin  +*ycin$, clarithromycin  ia#in$, and a!ithromycin  -ithroma#$. ã luoroquinolones such as ciproflo#acin  (ipro$, levoflo#acin  /evaquin$, and oflo#acin  lo#in$. ã &ulfonamides such as cotrimo#a!ole actrim$ and trimethoprim  'roloprim$ ã Tetracyclines such as tetracycline &umycin, 'anmycin$ and do#ycycline ibramycin$ ã Aminoglycosides such as gentamicin  aramycin$ and tobramycin  Tobre#$ *ost antibiotics have 2 names, the trade or brand name, created by the drug company that manufacturesthe drug, and a generic name, based on the antibiotic3s chemical structure or chemical class. Trade namessuch as )efle# and -ithroma# are capitali!ed. enerics such as cephale#in and a!ithromycin are notcapitali!ed.  How do antibiotics work? &ome antibiotics work by killing bacteria or the parasite. This is often done by interfering with thestructure of the cell wall of the bacterium or parasite. &ome work by stopping bacteria or the parasite frommultiplying.  ew Antibiotics!lassGeneric#rand /ipopeptides4aptomycin (ubicin$, 2005luoroquinoloneemiflo#acin active$, 2005/ipoglycopeptidesTelavancin ibativ$, 2006(ephalosporin 7th generation$(eftaroline Teflaro$, 2010*acrocyclicsida#omicin 4ificid$, 2011 $%&actam Antibiotics etalactam antibiotics include penicillins, cephalosporins, monobactams, and carbapenems. 'enicillinsGeneric#rand ame Amo#icillinAmo#il, 'olymo#, Trimo#, 8ymo#Ampicillin9mnipen, 'olycillin, 'olycillin:,'rincipen, Totacillin  ntibiotics work in two different ways either by killing the bacteria or blocking its function. They onlyattack the bacterial population present in the body and causing the disease, they do not affect the cell of the body. ;t is an unfortunate fact that though antibiotics are being used constantly but now bacteria havedeveloped resistance against these drugs. ;t is a very natural process that new antibiotics with moreeffectiveness are being developed and bacterial genome is revolutioni!ing against these newlysynthesi!ed antibiotics. An antibiotic has also the ability to convert glucose  in the body into energy. ;t produces a protective wallagainst bacteria and does not allow them to enter the cell. ;t also protects the body from further infectionand prevents the bacteria to multiply in number. Though antibiotics are useful in curing the human body against bacterial infections  but they also havesome side effects. A patient can suffer from slight headache to e#treme allergic reaction. Another sideeffect is diarrhea in which the balance of the intestinal flora gets affected and disrupts the function of theuseful bacteria present in the intestine. ;n some cases, antibiotics can react with other drugs administeredalong with them and cause other infections.;n the past before the discovery of antibiotics, the diseases like cholera  and diarrhea  would be fatal asthese diseases dehydrate the body and makes the individual weak. Antibiotics have the credit of saving somany lives by killing the microbes  causing certain diseases. ;n the disease of tuberculosis, antibiotics play an important role in eradicating the bacteria. To protect the patient from having side effects, doctors prescribe such antibiotics which suit person<s body. A summary of the main effector defense mechanisms against e#tracellular bacteria. acteria that avoiddestruction by the classical or alternative complement pathways may be opsoni!ed by acute phasereactants or specific antibodies and engulfed by phagocytes e#pressing receptors for the c region of these antibodies. he first generation  cephalosporins include= Their spectrums of activity are quite similar. They possessgenerally e#cellent coverage against most grampositive pathogens and variable to poor coverage againstmost gram negative pathogens. The first generation includes= ã cephalothin ã cefa!olin ã cephapirin ã cephradine ã cephale#in ã cefadro#il ã The second generation  cephalosporins. ;n addition to the gram positive spectrum of the firstgeneration cephalosporins, these agents have e#panded gram negative spectrum. (efo#itin andcefotetan also have good activity against acteroides fragilis. +nough variation e#ists betweenthe second generation cephalosporins in regard to their spectrums of activity against most speciesof gram negative bacteria, that susceptibility testing is generally required to determine sensitivity.The second generation includes= o cefaclor  o cefamandole  o cefonicid o ceforanide o cefuro#ime The third generation  cephalosporins have much e#panded gram negative activity. >owever, somemembers of this group have decreased activity against grampositive organisms. They have the advantageof convenient administration, but they are e#pensive. erusing antibiotics   There is concern worldwide that antibiotics are being overused. Antibioticoveruse is one of the factors that contributes towards the growing number of bacterial infections whichare becoming resistant to antibacterial medications.Antibacterial action generally falls within one of four mechanisms, three of which involve the inhibitionor regulation of en!ymes involved in cell wall biosynthesis, nucleic acid metabolism and repair, or proteinsynthesis, respectively. The fourth mechanism involves the disruption of membrane structure. *any of these cellular functions targeted by antibiotics are most active in multiplying cells. &ince there is oftenoverlap in these functions between prokaryotic bacterial cells and eukaryotic mammalian cells, it is notsurprising that some antibiotics have also been found to be useful as anticancer agents. Antibiotic Grouping #y *echanism (ell 8all &ynthesis'enicillins(ephalosporinsancomycinetalactamase ;nhibitors(arbapenemsA!treonam'olymycinacitracin'rotein &ynthesis ;nhibitors;nhibit 50s &ubunitAminoglycosides gentamicin$Tetracyclines;nhibit 70s &ubunit*acrolides(hloramphenicol(lindamycin/ine!olid &treptogramins4:A &ynthesis ;nhibitorsluoroquinolones *etronida!ole?:A synthesis ;nhibitors?ifampin*ycolic Acid synthesis inhibitors;sonia!idolic Acid synthesis inhibitors&ulfonamidesTrimethoprim

Lecture 1

Jul 23, 2017
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks