4. Antibiotics

Question 1

Define bacteriocidal

Answer 1

Any substance that kills bacteria/organism

Question 2

Define bacteriostatic

Answer 2

Biological or chemical agent that stops bacteria from reproducing (not necessarily killing them)

Question 3

What are the most frequently used antibiotics in dentistry?

What is their MoA?
What two primary antibiotics are included in this type?

Answer 3

1. Beta lactam’s
2. Disrupt cell wall
3. Penicillins/cephalosporins

Question 4

Bacteria are resistant to beta-lactams how?

Answer 4

Beta-lactamase production

Question 5

Penicillin

• Absorption is influenced by what?
• Narrow or wide distribution?
• Excretion how?

Answer 5

1. Gastric acid and food
2. Wide distribution
3. Renal excretion

Question 6

Pen VK

• MoA (2)
• Absorbed where?

Answer 6

1. Inhibits bacterial wall synthesis by binding to 1 or more penicillin-binding proteins
2. Bacteria lysis due to ongoing cell wall autolytic enzyme activity
3. Absorbed in stomach

Question 7

Pen Vk

- Dental uses (4)

Answer 7

Orofacial infections including cellulitis, peri-apical abscess, periodontal abscess, pericoronitis

Question 8

Pen Vk

- What is our main concern with Pen VK?

Answer 8

Multiple resistant bacteria

- S. aureus, S. pneumonia, B. fragilis, B. anthracis

Question 9

Pen G

• MoA
• Absorption?

Answer 9

Interferes with bacterial wall synthesis during active multiplication, causing cell wall death resulting in bactericidal activity against susceptible bacteria

• Absorbed intra-muscularly

Question 10

Amoxicillin

• MoA
• Absorption?

Answer 10

1. Inhibits bacterial wall synthesis by binding to one or more penicillin-binding proteins
2. Bacteria lysis due to ongoing cell wall autolytic enzyme activity
3. Absorption via GI tract

Question 11

Amoxicillin

• Dental concerns and medical concerns
• 4 general uses for it?

Answer 11

1. Candiasis and anaphylaxis
2. Med: Renal impairment
3. Orofacial infections, UTI’s, pneumonia, skin infections

Question 12

Amox plus Clavulanic acid

• Otherwise known as?
• Dental use?

Answer 12

1. Augmentin

2. Treatment of orofacial infections when beta-lacatamase producing staph and bacteroides are present

Question 13

Amox plus Clavulanic acid

- MoA

Answer 13

Clavulanic acid inds and inhibits beta-lactamase that inactivate amoxicillin resulting in amoxicillin having an expanded spectrum of activity
2. Amox inhibits bacterial cell wall synthesis by binding to 1 or more penicillin-binding proteins; bacterial lysis due to ongoing cell wall autolytic enzyme activity

Question 14

Penicillin (in general)

- Adverse effects

Answer 14

1. Anaphylaxis
2. Fever
3. Vasculutis
4. Rash
5. Stevens-Johnson syndrome

Question 15

Cephalosporin

• Bacteriostatic or cidal
• Excreted how?
• Cross-allergy with?

Answer 15

Bacteriocidal
Excreted via kidneys
Cross-allergy with penicillin

Question 16

Aminoglycosides

- Include which three?

Answer 16

Gentamycin, neomycin, streptomycin

Question 17

Neomycin (an amino glycoside)

• Use?
• MoA
• Absorption
• Contraindication

Answer 17

1. Surgical prophylaxis
2. Interferes with bacterial synthesis by binding to 30S ribosomal subunits
3. Oral absorption poor
4. GI obstruction (patients with IBD or ulcerative GI disease)

Question 18

Gentamycin (an amino glycoside)

• Use?
• MoA
• Absorption

Answer 18

1. Treatment of serious infections (sepsis, meningitis, UTI’s)
2. Interferes with bacterial synthesis by binding to 30S ribosomal subunits
3. IM rapid (oral poor)

Question 19

Streptomycin (an amino glycoside)

• Use?
• MoA
• Absorption

Answer 19

1. Treatment of TB, plague, etc
2. 2. Interferes with bacterial synthesis by binding to 30S ribosomal subunits
3. IM well absorbed (oral poor)

Question 20

Macrolides

• Bacteriostatic or cidal
• MoA

Answer 20

Bacteriostatic

Inhibit RNA-dependent protein synthesis by binding to 50s ribosomal subunit

Question 21

Macrolides

- What conditions are they a drug of choice?

Answer 21

1. Mycoplasma pneumonia, Legionaire’s disease

2. Subacute bacterial endocarditis

Question 22

Lincosamide (clindamycin)

• MoA?
• It’s more active against aerobes or anaerobes?

Answer 22

Reversibly binds to 50s ribosomal subunit inhibiting bacterial protein synthesis
More active against anaerobes

Question 23

Lincosamide (clindamycin)

• Absorption
• Metabolized where?
• Side effects
• How to treat side effect
• Signs/symptoms of side effects

Answer 23

1. Absorbed orally
2. Hepatic metabolism
3. Psuedomembraneous colitis (in 0.01-10%) and metallic taste
4. Administer vancomycin or metronidazole
5. Diarrhea, ab pain, fever

Question 24

Fluoroquinolone includes which four drugs?

Answer 24

1. Ciprofloxacin (good for anthrax)
2. Gemifloxacin
3. Levofloxacin
4. Ofloxacin

Question 25

Ciprofloxacin (a fluoroquinolone) - MoA - Absorption?

Answer 25

Inhibits DNA-gyrase in susceptible organisms (inhibits relaxation of supercoiled DNA and promotes breakage of double stranded DNA) - Rapid absorption in GI

Question 26

Tetracycline medications include? (3)

Answer 26

Tetracycline, doxycycline, and minocycline

Question 27

What are dental concerns with tetracycline meds?

Answer 27

1. Enamel hypoplasia 2. Esophagitis 3. Glossitis 4. Superinfections 5. Permanent teeth discoloration 6. Candida superinfection

Question 28

What was the initial "broad spectrum antibiotic? - MoA? - Extensive use has led to what?

Answer 28

Tetracycline Inhibits bacterial protein synthesis by binding to 30s ribosomal submit and possibly 50s ribosomal subunit. Resistance

Question 29

Tetracycline - Absorption can be impaired by? - Narrow or wide distribution? - Excretion?

Answer 29

1. Calcium, dairy, aluminum hydroxide gels 2. Wide distribution 3. Renal and fecal excretion

Question 30

buy AT 30, CELL at 50

Answer 30

Aminoglycosides and tetracyclines are 30s ribosomal subunit | Clindaymycin, erythromycin,