Pharmacology Chapter 83

Penicillins

-Weaken the cell wall, causing bacteria to take up excessive water and rupture
-Bactericidal*=kill

Inactivation of penicillins by bacterial enzymes
*Penicillins & Cephalosporines are both beta-lactams*

the Inability of penicillins to reach their target

Pencillinase sensitive
(are antistaphlococcal)
-Pencillinase resistant = are antistaphlococcal)
-Staphlococcus produces antipenicillin enzymes
*Staph makes penicillinase enzymes*

Extended spectrum penicillin, referred as antipseudomonal

Narrow spectrum effective against staph. species
*only know that narrow spectrum penicil-resist penicil do.*

-Immediate (2 to 30 minutes)
-Accelerated (1 to 72 hours) *begins to form a rash*
-Late (days or weeks) *VERY RARE*

-Laryngeal edema
-Bronchoconstriction
-Severe hypotension
*NOT N/V, yeast infection, diarrhea…**

-Epinephrine
-Respiratory support
-Prevention—skin testing *by scratching skin & rubbing penicillin on skin*

Allergy—penicillins are the MOST common cause of drug allergy*** BUT they’re the most widely used antibiotics**

Same coverage as narrow but increased gram negative coverage
Better penetration into cell envelope.
The aminopenicillins :
-Ampicillin
-Amoxicillin

Adverse effects:
-Rash
-Diarrhea**b/c penicillins interfere w/ gut flora 

Same coverage as Aminopenicillin PLUS pseudomonas.
The extended spectrum penicillins consist of
4 agents:
-Ticarcillin
-Carbenicillin indanyl
-Mezlocillin
-Piperacillin

Stops destruction of PCN by penicillinase= boosts ability to kill more bacteria*
Blocks the enzyme synthesized by bacteria to stop the enzymes targeted by our drugs

The beta-lactam ring is
what kills bacteria**
: IF THERE’S NO BETA LACT. RING THEN THERE IS NO EFFECTIVE ANTIBIOTIC, IF THE RING IS BROKEN OR OPEN NOTHING WILL WORK!! THE BETA RING IS THE MOST IMPORTANT PART OF THE PNC STRUCTURE**