Cell Wall Synthesis I Flashcards
Cell Wall Synthesis Inhibitors fxn?
Inhibit cell wall synthesis is one of the most common modes of action for antibiotics. By inhibiting peptidoglycan synthesis, the growth of bacteria is prevented. These bacteria will be subjected to osmotic lysis.
New
Cell wall synthesis inhibitors classes?
YOYO
Don’t make the same mistake
BBPF
B-latactams
Peptide
Fosfomycin
Bacitracin
Penicillins drugs?
BANN
- Natural penicillins: Penicillin G & V
- B-lactamase resistant
- Broad spectrums penicillins
- Antipseudomonal Penicillins
B-lactam drugs-4?
- Penicillins
- Cephalosporins
- Carbapenems
- Monobactams
Natural Penicillin drugs?
Penicillin G
Penicillin V
Natural Penicillin
-Spectrum
-B-lactam sensitivity
-Narrow spectrum
-B-lactamase sensitive
B-lactam MOA?
Inhibit transpeptidase enzyme
Penicillin G synonym
Benzylpenicillin
Penicillin G indications AND admin?
-Infective endocarditis syphilis
-Syphillis
Admin: IM/IV
Penicillin G prophylaxis-3?
SRS
-Streptococcal infections
-Rheumatic fever
-Surgical or dental procedures on patients with valvular heart disorders
Penicilin G line oof therapy and why
The initial line of therapy for serious infections after resolved then switch to Penicillin V.
Penicillin G has increased S/E and very potent
Penicillin V synonym?
Phenomethyl-penicillin
Penicillin V
-Admin
-Effectiveness against Penicillin G
-Follow up treatment
-Oral
-2-4 times less active than Penicillin G
-Follow up antibiotic treatment after serious infections responded well to Penicillin G
B-lactamase resistant penicilin drugs-3?
-Cloxacillin
-Flucloxacillin
-Methicillin
B-lactamase resistant penicilin
-Effectiveness
-Treatment
-Slightly less active than Pen G
-Treatment of mild B-lactamase-positive staph. infections
Antipseudomonal penicillin drugs?
-Piperacillin
-Tazobactam(B-lactamase inhibitor)
Tazobactam?
B-lactamase inhibitor
Given adjunct with Piperacillin
Antipseudomonal penicillin most active against?
Most active against P.aerugunosa
Antipseudomonal penicillin synergistic action?
Acts synergistically with aminoglycosides for empiric treatment of serious Pseudomonas infections
Broad spectrum penicillins
Broad spectrum penicillins/Aminopenicillins chemical structure to make it better absorbed?
Amino side-chain is hydrophilic
Makes it easier for them to penetrate through the other membrane of Gram -ve bacteria
Broad spectrum penicillins/Aminopenicillins drugs and sensitivity ?
Amoxicillin & Ampicillin
They are B-lactamase resistant and thus have to be taken with an additional drug
Amoxicillin + Clavulanic acid
Ampicillin +Cloxacillin
Amoxicillin
-Adjunct drug/Combination name
-Trade name
-B-lactamase resistant
-Adjunct drug/ Combination name:
Amoxicillin + Clavulanic acid=Co-amoxiclax
-Trade name:
Augmentin
-B-lactamase resistant:
B-lactamase resistant
Clavulanic acid mOA and bacterial activity?
Clavulanic acid binds to B-lactamase enzyme and prevents the degradation of amoxicillin
Thus, no antibacterial activity
Ampicillin +Cloxacillin?
-Has extended spectrum
-Cloxacillin is just B-lactamase resistant. It does not actually protect against the degradation of B-lactamase for Ampicillin
Penicillins S/E-6?
PENCILLIN
-Agranulocytosis( ↓ WBC)
-Convulsions ( @↑ doses of Pen G)
-Anaphylactic shock (Hypersensitivity reactions)
-Bleeding( ↓ platelet aggregation) (Pen G & Piperacillin)
-↓ Efficacy of combined oral contraceptives
-Cholestatic hepatitis & Jaundice(Fluxloxacillin & Clavulanic acid)
Which drug causes bleeding for penicillins?
Pen G & Piperacillin
Which drug causes cholestatic hepatitis & jaundice for penicillins?
Flucloxacillin & Clavulanic acid
Penicillin DI-4?
-Probenecid(↑ t1/2 of penicillin)
-Aminoglycosides + Penicillins=Should not be adminstered in the same syringe, infusion or IV line as they deactiavte each other
-Allopurinol (Skin rash)
-Combined oral contraceptives-Penicillin ↑ oestrogen levels ∴
Pregnancy
Penicillin pharmacokinetics-5?
-Extended action of Pen G
-Inflammation ( ↑ penetration into CSF and synovial fluid)
-Probenecid(↑ t1/2)
-↑ doses, conc above MIC
-Depot formulation via IM injection(Procaine & Benzathine
Penicillin CI-4?
-Allergic patients
-↓ renal function ∴
toxicity:
-Elderly &
Neonates
-Porphyria (Flucloxacillin)
-Co-amoxiclav excreted in breast milk ∴ caution during lactation
Penicillin Mechanism of resistance?
- B-lactamase production(Penicillinase)-hydrolysis of B-lactam ring ∴ inactivation
- Absence of a cell wall
- Mutations
- ↓ Membrane Permeability
- Lack of autolysins
- Altered penicillin binding proteins
- Metabolically inactive bacteria
Cephalosporins
-Derivative
-Chemical structure
-Stability
-Derivative:
Semi-synthetic antibiotics-derived from penicillins but synthesized in the lab
-Chemical structure:
Contain a B-lactam ring. If a patient is allergic to penicillins then they are likely to be allergic to cephalosporins
-Stability:
↑ stability against B-lactamases compared to penicillins
Cephalosporins mechanisms of resistance-5?
- B-lactamase production(Cephalosporins )
- ↓ Permeability
- No cell wall
- Bacteria do not grow
- Alterations in binding proteins
Cephalosporins classes of drugs
ZoRoTaPi
- Zolidroxin
Cefalexin
Cefadroxil
Cefazolin - Roxitinmandole
Cefuroxime
Cefoxitin
Cefamandole
Cefprozil - Taxixone
Cefotaxime
Ceftriaxone - Piropime
Cefepime
Cefpirome - Ceftaroline
Which bacteria do cephalosporins treat?
-Gram +ve only
-Strep & Staph
Cefamandole S/E?
-Disulfiram-like reactions
-↑ acetaldehyde ∴ alcohol intolerance
Cephalosporins 3rd generation and CNS?
-Crosses BBB
-Penetrates CSF easily
Thus, can treat meningeal infection
