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Home , Bacampicillin

Krysia Hudson Diane Aschenbrenner

Principles of Antimicrobial Therapy

 Antivirals treat viruses  Antibiotics do NOT treat viruses  Antimicrobial drugs are classified by their susceptible organism or by their mechanism of action  Empiric or broad spectrum treatment  Sensitivity  Resistance  Selective Toxicity

Terms

 Bacteriostatic  Prophylaxis

 Bactericidal  Selective toxicity

 Culture  Peak and Trough

 Sensitivity Levels

 Nosocomial  Anaerobic

 Gram –  Aerobic

 Gram +

1 What is an infection?

 How does it present?  Fever above 101F  Malaise

What is a virus?

 How does it present?  Malaise  Temperature below 101F

Selection of Antibiotics

 Effectiveness against specific bacteria causing the infection

 Sensitivity of the organism to the drug

 Ability to get to the site of the infection

 Causing the fewest adverse effects in patients

2 (prototype: G)

PT: treat infections (gram + and some gram -) Prophylaxis bacterial endocarditis

Prevvy,ents synthesis, cell wall swells and bursts PK: oral absorption affected by GI acidity Unchanged thru kidneys Dosing must be round the clock to be effective

Penicillins

AE: Anaphylaxis , GI complaints Pt Related Variables: allergies, birth control pills Maximize Effects: C & S, give on time, gi ve fllfull course o f therapy, Assess s/s of infection Minimize Effects: Treat s/s of GI distress (ice chips, etc) Assess for allergic reactions

Other Penicillins

Penicillin V Procaine Penicillin (treat gonorrhea) give IM (very thick) keep refidfridgera te d assess for allergy (confusion, agitation)

3 Other Penicillins

Aminopenicillins PT: otitis media, URI, tonsillitis, skin infections, pneumonia Effective against Gram – Alternate to Pen G and Pen V (when they don’t work) Examples: , , bacampicillin

Extended Spectrum Penicillin

PT: SERIOUS infections (pseudomonal and proteus infections) AE: Direct tissue toxicity (dose related) muscle twitching, seizures, decreased function of platelets Nsg Mgmt: available of Na salt (possible hypernatremia) Examples: , , pipericillin,

Penicillinase - Resistant Penicillin (, , )

PT: Treat organisms that secrete the enzyme penicillinase Needs C&S, if patient is resistant to methicillin (MRSA), it is resistant to anyyg drug in this class

4 (Prototype: )

PT: Respiratory, urinary, bone, skin, ear infections, Gram + PK: does not cross blood brain barrier, does cross placenta, excreted unchanged in urine PD: chemical structure similar to PCNS, interferes with cell wall synthesis AE: common GI, nephrotoxicity (with those with renal insufficiency), superinfections pseudomembranous colitis, hypersensitivity (rash) Nsg: may be given with food or fluid to decrease GI distress

Vancomycin (Tricyclic glycopeptide)

PT: SERIOUS INFECTIONS (Gram + infections, PCN and MRSA resistant infections), synergistic use with aminoglycosides for Strep and MRSA PK: oral dose – low bioavailability, used for GI infections (Pseudomembranous colitis) after use of metronidazole With normal renal function ½ life is 4-6 hrs, with IV administration, excreted mostly thru kidneys

Vancomycin (Tricyclic glycopeptide)

Cautions: Pregnancy, renal issues AE: Ototoxicity, nephrotoxicity Red Man’s Syndrome – histamine release [give over 1 hour] NSG: Peak and Trough (30 mi n pri or to gi vi ng) , 1 hour aft er Monitor hearing BUN and creatinine, urine output Ototoxicity can be spurned by excessive dose, prolonged exposure, dehydration, other ototoxic drugs, bacteremia Ototoxicity can also come in the form of ataxia and nystagmus

5 Summary

 General infection principles

 Antibiotics:  Affect bacterial cell wall  PCNs   Vancomycin

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