Antibacterial Agents Review

What color do gram negative bacteria stain?

Pink/ red

What color do gram positive bacteria stain?

Purple/ blue

What color do gram negative bacteria stain?

Pink/ red

What color do gram positive bacteria stain?

Purple/ blue

Gram positive bacteria

• streptococci: oral infections

• enterococci: UTIs

• staphylococci: skin/ soft tissue infections

  • MSSA: penicillin sensitive

  • MRSA: penicillin resistant

• Clostridioides

  • C. difficile: diarrhea

Gram Negative bacteria

• pseudomonas: hospital infections

• helicobacter: community GI/stomach infections

• E.coli: GI, travelers diarrhea, UTIs

• Klebsiella: UTI, diarrhea

• Bacteroides: oral cavity infections

What bacteria is responsible for hospital infections? Gram pos or negative?

pseudomonas, gram negative

What bacteria is responsible for travelers diarrhea? Gram pos or neg?

E. coli, gram negative

What gram neg bacteria is responsible for oral cavity infections?

Bacteroides, gram neg

What gram pos bacteria is responsible for oral infections

streptococci

C.difficile causes?

diarrhea

Beta-lactams MOA

• work on bacterial cell wall

  • inhibit the synthesis of the cell wall

Beta-lactams examples?

• penicillin family

• cephalosporine family

What class are penicillins and cephalosporines?

Beta-lactams

Beta-lactams, penicillins examples

• Penicillin

• Ampicillin

• Amoxicillin

• Amoxicillin-clavulante

Beta- lactams, cephalosporins examples

• Cefadroxil

• cefazolin

• cephalexin

• cefuroxime

• ceftriaxone

• ceftaroline: MRSA infections

Criteria for a drug reaction to be considered immunologically mediated; true allergy

• reaction in small number of patients

• reaction does not resemble drug’s pharm effects

• reaction w/ small amount of drug

• reaction w/ drugs w/ similar structures

• reaction resolves after discontinuation

What % of patients report a PCN allergy?

10-20%

Out of the 10-20% of pts who report a PCN allergy, what % of them are true allergies?

less than 10%

True allergic reaction symptoms?

• skin rash, hives

• difficulty breathing including wheezing

• dizziness and hypotnsion

True allergic reaction “kit”

• epi pen

• antihistamine

Macrolides examples

• azithromycin

• clarithromycin

• erythromycin

Azithromycin, clarithromycin, erythromycin drug class?

macrolides

Macrolides: Azithromycin, clarithromycin, erythromycin MOA

• inhibit bacterial ribosome

  • inhibit protein synthesis

Clindamycin MOA

binds to 50 S ribosomal subunit and inhibits protein synthesis

Clindamycin coverage

• gram positive coverage

  • anaerobic coverage

Clindamycin ADRs

GI, diarrhea

Why are clindamycins no longer used in dent?

resistasnce

When is Antibiotic prophylaxis suggested?

• prosthetic cardiac valve or materia

• previous, relapse, or recurrent IE

• CHD

• Cardiac transplant recipients who develop cardiac valvulopathy

Amoxicillin situation and adult dose

oral, 2g

Ampicillin situation and adult dose

unable to take oral med, 2g

Cefazolin or ceftriaxone situation and adult dose

allergic to penicillin or ampicillin and unable to take oral, 1g

Cephalexin situation and adult dose

allergic to penicillin or ampicillin- oral, 2g

Azithromycin or clarithromycin situation and dose

allergic to pencillin or ampicillin- oral, 500mg

Doxycycline situation and adult dose?

allergic to penicillin or ampicillin- oral, 100mg

What % is chlorhexidine rinse?

15 ml of 0.12% solution

oropharyngeal candidiasis troches

clotrimazole troches

oropharyngeal candidiasis suspension

nystatin suspension

oropharyngeal candidiasis tablet

fluconazole tablet