Everytime I learn something, I will expand these notes.
History
- First antibiotic, which was penicillin was introduced around 1940. Dr. Alexander Flemming showed its discovery potential in 1929, and an Oxord team (Dr. Howard Florey et al.) elaborated this work further in the US. As well Dr. Flemming, Dr. Florey and his team won Nobel Prize later on.
(You can see some of the instruments that Dr. Florey and colleagues used in the Museum of the History of Science in Oxford (pics). It's for free!)
- Within 5 years the first resistant isolates to penicillin was already shown.
- A large number of antibiotics was discovered between the 50s and 70s. Vancomycin was among the antibiotics discovered in these years and perhaps vancomycin is one of the most succesful antibiotic against the resistance problem. It took about 25 years before first resistance to vancomycin was shown.
- It is increasingly difficult to discover new antibiotics. Among new antibiotics are daptomycin (around 2004) and ceftobiprole.
Classes
It is quite difficult to remember all the antibiotics. Its better to learn them in term of classes than by remembering all the names. The classes are based on the working mechanisms or on the structure of antibiotics.
Penicillin and other beta-lactam
- mainly work by destroying cell wall.
- active against Gram + and Gram -
- can be classified as into:
- natural penicilline (e.g. penicilline G (i.v.), penicilline V (oral)
- antistaphylococcal penicillin (many are beta-lactamase resistant), e.g. nafcillin, oxacillin, methicillin
- broad spectrum (can be divided further in classes, from low--> high: ampicillin, ticarcillin, piperacillin)
- patients can be allergy to penicillin.
Cephalosporine
- beta-lactam antibiotics
- there are 5 generations. From low --> high: in general better against Gram negative and vice versa.
- first generation (e.e. cephazolin) is used as antibiotic prophylaxis for surgical site infection (SSI). SSI is mostly caused by Gram + bacteria.
- 6% patients allergy to penicillin also allergy to cephalosporine.
Carbapenem
- i.e. imipenem, meropenem, ertapenem.
- broad spectrum.
- often last resort, until the emerging of CPE.
Alternative for penicillin
Glycopeptide
- inhibits proteoglycan chain elongation.
- alternative for penicllin in case of resistance.
- i.e. vancomycin (can cause necrosis and phlebitis at injection site) and teicoplanin.
- i.v. except in C.difficile associated diarrhea oral.
- mainly against Gram positive.
Linezolid and Daptomycin
- These new antibiotics are not from the same classes but they are the alternative in case of vancomycin resistance or when vancomycin can not be given (i.e. kidney problem).
Antibiotics that work on protein synthesis
- Mnemonics: CLEAN (clindamycin, chloramphenical and erythromycine (a macrolide) that work by binding with 50S ribosome subunit and TAG (tetracycline and aminoglycosides) that work by binding on 30S ribosome subunit.
- Mostly these antibiotics are bacteriostatic.
- Antibiotics that works on 50s ribosome subunit
- Chloramphenicol (very broad spectrum, side effects among others: aplastic anemia, Gray baby syndrome, still widely used in low-income countries).
- Macrolide (classified based on number of C-atoms in macrolide ring, from 14C to 16C --> erythromycin, azithromyzin, spiramycin).
- Antibiotics that works on 30s ribosome subunit
- Tetracycline (broad spectrum, tetracyline is natural, doxycycline is semi-synthetic, dosyxcyxline is good agains intracellular bacteria such as Rickettsiae en Chlamydiae)
- Aminoglycosides (e.g. gentamycin, streptomycin, variability in dose given and plasma level --> drug monitoring needed).
Antibiotics that inhibits DNA replication
- quinolones (from 1st generation --> 4th: nalidixic acid, ciprofloxacin, levofloxacin, movifloxacin).
- broad spectrum: inhibition of DNA gyrase (Gram -) and topoisomerase type IV (Gram +) enzymes.
Antibiotics that inhibits RNA
- Rifampicin
History
- First antibiotic, which was penicillin was introduced around 1940. Dr. Alexander Flemming showed its discovery potential in 1929, and an Oxord team (Dr. Howard Florey et al.) elaborated this work further in the US. As well Dr. Flemming, Dr. Florey and his team won Nobel Prize later on.
- Within 5 years the first resistant isolates to penicillin was already shown.
- A large number of antibiotics was discovered between the 50s and 70s. Vancomycin was among the antibiotics discovered in these years and perhaps vancomycin is one of the most succesful antibiotic against the resistance problem. It took about 25 years before first resistance to vancomycin was shown.
- It is increasingly difficult to discover new antibiotics. Among new antibiotics are daptomycin (around 2004) and ceftobiprole.
Classes
It is quite difficult to remember all the antibiotics. Its better to learn them in term of classes than by remembering all the names. The classes are based on the working mechanisms or on the structure of antibiotics.
Penicillin and other beta-lactam
- mainly work by destroying cell wall.
- active against Gram + and Gram -
- can be classified as into:
- natural penicilline (e.g. penicilline G (i.v.), penicilline V (oral)
- antistaphylococcal penicillin (many are beta-lactamase resistant), e.g. nafcillin, oxacillin, methicillin
- broad spectrum (can be divided further in classes, from low--> high: ampicillin, ticarcillin, piperacillin)
- patients can be allergy to penicillin.
Cephalosporine
- beta-lactam antibiotics
- there are 5 generations. From low --> high: in general better against Gram negative and vice versa.
- first generation (e.e. cephazolin) is used as antibiotic prophylaxis for surgical site infection (SSI). SSI is mostly caused by Gram + bacteria.
- 6% patients allergy to penicillin also allergy to cephalosporine.
Carbapenem
- i.e. imipenem, meropenem, ertapenem.
- broad spectrum.
- often last resort, until the emerging of CPE.
Monobactam
- i.e. Aztreonam
- against Gram negative.
- 'destroy' cell wall.
- mainly treatment of P. aeruginosa in cystic fibrosis patients.
- i.e. Aztreonam
- against Gram negative.
- 'destroy' cell wall.
- mainly treatment of P. aeruginosa in cystic fibrosis patients.
Glycopeptide
- inhibits proteoglycan chain elongation.
- alternative for penicllin in case of resistance.
- i.e. vancomycin (can cause necrosis and phlebitis at injection site) and teicoplanin.
- i.v. except in C.difficile associated diarrhea oral.
- mainly against Gram positive.
Linezolid and Daptomycin
- These new antibiotics are not from the same classes but they are the alternative in case of vancomycin resistance or when vancomycin can not be given (i.e. kidney problem).
Antibiotics that work on protein synthesis
- Mnemonics: CLEAN (clindamycin, chloramphenical and erythromycine (a macrolide) that work by binding with 50S ribosome subunit and TAG (tetracycline and aminoglycosides) that work by binding on 30S ribosome subunit.
- Mostly these antibiotics are bacteriostatic.
- Antibiotics that works on 50s ribosome subunit
- Chloramphenicol (very broad spectrum, side effects among others: aplastic anemia, Gray baby syndrome, still widely used in low-income countries).
- Macrolide (classified based on number of C-atoms in macrolide ring, from 14C to 16C --> erythromycin, azithromyzin, spiramycin).
- Antibiotics that works on 30s ribosome subunit
- Tetracycline (broad spectrum, tetracyline is natural, doxycycline is semi-synthetic, dosyxcyxline is good agains intracellular bacteria such as Rickettsiae en Chlamydiae)
- Aminoglycosides (e.g. gentamycin, streptomycin, variability in dose given and plasma level --> drug monitoring needed).
Antibiotics that inhibits DNA replication
- quinolones (from 1st generation --> 4th: nalidixic acid, ciprofloxacin, levofloxacin, movifloxacin).
- broad spectrum: inhibition of DNA gyrase (Gram -) and topoisomerase type IV (Gram +) enzymes.
Antibiotics that inhibits RNA
- Rifampicin
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