PHARM Antibacterials

Penicillin (PCN)
Chemical structure

beta-lactam

PCN V

Oral - for mild to moderate infection

PCN G

parenteral IV

Procaine G

Only IM - numbing agent added

Assessment for PCN

PCN & cephalosporin allergy

penicillinase

Bacteria produce enzyme to destroy the antibiotic

(Amoxicillin w/clavulanic acid) Augmentin

Combine PCN with other agents to prevent destruction by enzyme

PCN Side effects

Hypersensitivity- allergic reactions
GI symptoms- N & V, diarrhea
destroys normal GI flora
Renal impairment
Superinfection

How many generations does cephalosporin have?

4 generations: each new generation is more resistant to being inactivated and more expensive
Ceftin, Cephalexin, Cefaclor, Zinacef

Cephalosporin side effects

GI upset
Nephrotoxic
Caution with renal impairment
Assess for allergies to PCN and Cephalosporin class due to cross-sensitivity

Macrolide Class

Prototype drug: Erythromycin

PCN substitute

Erythromycin (Macrolide class)

Macrolide

oral well absorbed, never give IM

Erythromycin IV

MUST dilute in 250 mL of fluid can cause phlebitis

Macrolide side effects

GI upset, N & V, hepatotoxic

NSG process for macrolide

check liver enzymes, AST, ALT

Extended macrolide group: longer half life

-Clarithromycin (Biaxin) taken BID
-Azithromycin (Zithromax) Z-Pak taken daily

Topical erythromycin

given to newborns to prevent gonorrheal eye infection.

Tetracycline

First broad spectrum antibiotic against gram neg and gram +
-Bacteriostatic

Tetracycline route

oral
IV if severe infection

can be used for acne treatment

Tetracycline

Tetracycline teaching

**Do NOT take with antacids, milk, calcium or iron- binds & prevents absorption
**Take on empty stomach
**Oral contraceptives are less effective with tetracycline!
**Discard outdated med ?breaks down into toxic byproduct

Tetracycline side effects

Photosensitivity
Superinfection
Teratogenic- effects last trimester of pregnancy thru age 8 of child, irreversibly discoloring permanent teeth (gray)

Long acting Tetracycline preparations:

doxycycline
minocycline

Aminoglycosides

-Primarily parenteral
-Prototype drug: Gentamicin (Garamycin)

Aminoglycosides side effects

ototoxicity
nephrotoxicity

Fluoroquinolones (Quinolones)

-Levofloxacin (Levaquin)
-Moxifloxacin (Avelox) pneumonia, skin (Above the waist)
-Ciprofloxacin (Cipro) good for urinary tract (Below the waist)

Moxifloxacin (Avelox)

pneumonia, skin (Above the waist)

Ciprofloxacin (Cipro)

good for urinary tract (Below the waist)

Vancomycin = Powerful antibiotic used for:

Staphylococcal infections
MRSA
Clostridium difficile (C-diff)

Vancomycin side effect

nephrotoxic
ototoxic

Vancomycin NSG process

-Draw peak to monitor serum levels
-monitor BUN & Creat
-hearing
-Get baseline hearing data, can have permanent or temporary loss

Vancomycin-If given too fast IV-

get Red Neck/Red Man Syndrome due to vasodilation - leads to hypotension & tachycardia