antibiotics Flashcards
list the beta lactams
penicillin
cephalosporins
carbapenems
monobactams
types of penicillin
narrow and broad spec
broad spec penicillins
Carboxypenicillin
Aminopenicillin
Ureidopenicillin
groups of antibiotics
- B lactams
- Glycopeptides
- Aminoglycosides
- Tetracycline
- Macrolides
- Amphenicols
- Lincosomide
- Fluoroquinolones
- Sulphonamides
- Nitroimidiazole
examples od nitromidazo;es
Metromidazol
b. Timidazol
principle for prescribing antibiotics
- MUST HAVE A BACTERIAL INFECTION (duh)
- Better to know type of MO
- character of the disease
- the patient
- pharmacological characteristics of the drug
- localization
- clinical manifestations
what type of antibiotic is given to immunosupressed patients
bacteriacidal
which factors infulence the efffective therapeutic concenctration at the site of infection
Cmax - max [serum] that a drug achieves in a specified compartment of a test area of the body before the 2nd dose. 2. Tmax – amount of time a drug is present at Cmsx 3. AUC – ‘area under the curve’ àtotal drug exposure across time. The curve represents total amount of drug absorbed by the body 4. T ½ 5. MIC – [lowest] of a drug which prevents visible growth of bacterium.
what is the Cmax
max [serum] that a drug
achieves in a specified compartment
of a test area of the body before the
2nd dose.
what is the t max
Tmax – amount of time a drug is
present at Cmsx
what is the AUC
area under the curve’ àtotal
drug exposure across time. The
curve represents total amount of
drug absorbed by the body
what is MIC (minimal inhibitory concentration)
[lowest] of a drug which
prevents visible growth of
bacterium.
how many types of antibiotics are there according to their absorption
type 1: aminoglycosides and fluroquinilones
type 2: b lactam
type 3: tetracycline and azithromycin
type 1: aminoglycosides and fluroquinilones absorption
Fast and powerful antibacterial effects - Less ADRs when peak conc achieved - Conc dependant effect!*] - ideal dose MUST ensure maximal high plasma conc
type 2 b lactams
highest bacterial efficacy when [serum] are 2-4 > MIC - ideal dose regimen is maximal duration of effect between 2 doses.
type 3 tetracylcines and azithromycin
Possess mixed type
pharmacokinetic and pharmaco
dynamics
application of aminoglycosides
single daily
dose application.
Ratio of Cmax/ MIC > 10
determines antibacterial effect.
flouroquinolones
à AUC/MIC
ratio
Gram +ve = 25-30
Gram -ve = 100-125
when should the antibiotic theraapy be changed
after 48-72 hours
Concentration dependent antibiotics: Aminoglycosides and flouroquinolones
ntibiotics which eradicate pathogenic bacteria by achieving high concentration at the site of binding
ntibiotics which eradicate pathogenic bacteria by achieving high concentration at the site of binding
Time dependent antibiotics: penicillins, cephalosporins, carbapenems, monobactams), clindamycin, macrolides (erythromycin, clarithromycin), oxazolidinones (linezolid).
he time that serum concentrations remain above the MIC during the dosing interval (t>MIC)”.They show optimum killing response when the time that the drug remains above the MIC is either equal or greater than 50% of the dosing interval.
when is combination therapy indicated
Avoid drug resistance especially in diseases like TB 2. Immunocompromised patients 3. Prophylaxis in heavy operations – i.e intraabdominal ops 4. Widening antimicrobial spectrum in critical cases i.e septicaemia 5. Rx of mixed infections (aerobes and anaerobes )
types of antibiotics based on mechanism of action
- Bactericidal effect on fast divided microbes + microbe spores – aminoglycosides, flouroquinolones
- Bactericidal effect on fast divided microbes – B lactams + vancomycin
- Bacteriostatic effect – Tertacycline , macrolides chloramphenicol, lincozamides morning
which combinations are profitable
group 1 and 2
group 1 and 3
group 2 and 2
group 3 and 3
