Antibiotics

Sulfonamides: bacteriostatic or bactericidal?

Bacteriostatic

Sulfonamide MOA

Folate synthesis inhibitor (competes w/PABA) -- folic acid deficiency impacts DNA of bacteria

Fluoroquinolones - bacteriostatic or bactericidal?

Bactericidal

Fluoroquinolones MOA

DNA synthesis inhibitor

What class are Ciprofloxacin & Levofloxacin?

Fluoroquinolones

Penicillins - bacteriostatic or bactericidal?

Bactericidal

Penicillin MOA

Cell wall synthesis inhibitor; B-lactam (broad spec) abx

What antibiotic class should be avoided in pts allergic to penicillin?

Cephalosporins (also B lactam abx)

Which penicillin is used IV only?

Pen G

Which penicillin is taken orally?

Pen V

What is augmentin?

amoxicillin + clavulanic acid (B lactamase resistant)

What penicillin has the best/broadest gram-negative spec?

Ampicillin

Which penicillin is used specifically against pseudomonas?

Carbenicillin

Cephalosporins - bacteriostatic or bactericidal?

Bactericidal

Cephalosporins MOA

Cell wall synthesis inhibitor, B-lactam

Monobactams - bacteriostatic or bactericidal?

Bactericidal

Monobactam MOA

Cell wall synthesis inhibitor, B lactam

Suffix for monobactams

-am

Carbapenems - bacteriostatic or bactericidal

Bactericidal

Carbapenems MOA

Cell wall synthesis inhibitor, B-lactam

Carbapenems suffix

-nem

Tetracyclines - bacteriostatic or bactericidal

Bacteriostatic

Tetracycline MOA

Protein synthesis inhibitor (30S ribosomal unit)

Of all the antibiotics, what has the broadest antimicrobial spectrum?

Tetracyclines

Macrolides - bacteriostatic or bactericidal

Bacteriostatic

Macrolides MOA

Protein synthesis inhibitor (50s subunit)

Macrolide drugs

Mac likes to throw miceMacrolides:-Erythromycin-Clarithromycin-Azithromycin

Lincosamides - bacteriostatic or bactericidal

Bacteriostatic

Lincosamides MOA

Protein synthesis inhibitor (50s)

Lincosamides drugs

Link also hides miceLincosamides:-Clindamycin-Lincomycin

Which compromised immunity conditions require abx prophylaxis?

-Organ transplant-Neutropenia-Cancer therapy

Which cardiovascular conditions need abx prophylaxis?

-Prosthetic heart valve-H/o endocarditis-Heart transplant w/valvulopathy/valve dysfunction-Congenital heart problems

What is the 1st choice for abx rx for IE prophylaxis?

Amoxicillin-Adult: 2g-Child: 50mg/kg

What is the first choice for rx for joint replacement abx prophylaxis?

Keflex 2g

When is abx prophylaxis not required?

-Cardiac pacemaker-Rheumatic fever without valvular dysfunction-Mitral valve prolapse w/o valvular regurgitation

What causes GI upset & pseudomonas colitis?

Clindamycin

What is most likely to cause superinfection?

Broad spectrum abx

What is associated with aplastic anemia?

Chloramphenicol

What is associated with liver damage?

Tetracycline

What is associated with allergic cholestatic hepatitis?

Erythromycin estolate

What should bacteriostatic drugs not be taken with?

Bactericidal

What should penicillin not be taken with?

Probenecid (gouty arthritis)

What should tetracycline not be taken with?

Antacids/dairy

What should broad spec abx not be taken with?

Anticoagulants (enhance bleeding by reducing vitamin K sources)

What should macrolides not be taken with?

Seldane (antihistamine)/digoxin (antiarrythmic)

Where does clindamycin concentrate?

Bone

Where does tetracycline concentrate?

gingival crevicular fluid

What antivirals are used to tx herpes?

Acyclovir, Valcyclovir

What antifungals are used for candidiasis?

Fluconazole, Ketoconazole

What form is clotrimazole (Mycelex)?

Troche form (lozenge that dissolves in your mouth)

Which penicillin is useful against penicillinase-producing bugs such as staphylococcus

Dicloxacillin

T/F abx prophylaxis is required for patients w/pulmonary shunts

true

Antifungal MOA

Bind ergosterol in fungal cell wall to weaken the wall

Penicillin allergy symptoms

-Dermatitis-Stomatitis-Bronchoconstriction-CV collapse

Which agent is least likely to cause superinfection

Narrow spectrum such as Pen G

Sulfonamides and trimethoprim are synergistic bacteriostatic agents because in bacteria theya) both inhibit folic acid synthesisb) interfere sequentially with folic acid productionc) are both antimetabolites of PABAd) are both inhibitors of dihydrofolic acid reductasee) are both transformed in vivo into a single active compound

b

The concurrent administration of Pen G and probenecid results in

Decreased renal excretion of Pen G

Interaction between penicillin & probenicid is best described by which of the following:a) competition at receptorb) acceleration of metabolismc) alteration in acid-base balanced) alteration in the rate of renal clearance

d

Erythromycin should be avoided in the patient takinga) aspirinb) seldanec) benadryld) ibuprofene) propranolol

B - may be lethal bc causes buildup of seldane which leads to cardiac arrhythmias