Antibiotics Drugs

Question 1

Sulfonamides

Answer 1

• Bacteriostatic
  
  • ​Inhibits bacterial growth by inhibiting folic acid synthesis
• Broad spectrum
  
  • Gram +/-
• Eliminated in the kidneys
  
  • Commonly used for UTIs
• Can be used in opportunistic infections r/t HIV & output tx of MRSA
• CI = Allergy
• S/E = allergic rxn
• Interaction: diabetes tx & oral contraceptives
  
  • potentiates hypoglycemic effect
• Sulfamethoxazole/ trimethoprim (Bactrim)

Question 2

Penicillins

Answer 2

• 1st derived from mold
• Bactericidal
  
  • kills gram +/- bacteria
  • but mostly gram +
• Interferes with wall synthesis
• Mostly safe & overall well tolerated
• S/E= allergic reaction
  
  • Includes urticarial, pruritus, angioedema
• CI = allergy
• Interactions: NSAIDs, oral contraceptive, Warfin
• Amoxicillin, Ampicillin, Penicillin G

Question 3

Cephalosporins

Answer 3

• Semi-synthetic and r/t penicillin
• Bacteriocidal
  
  • Interferes with wall synthesis
• Broad spectrum
• 5 different generations
  
  • 1st gen = > gram +
  • With each subsequent generation > gram - & anaerobic
• Cross sensitivity with penicillin
• S/E: similar to penicillins
• Cefazolin (Ancef); Cefoxitin (Mefoxin)

Question 4

Macrolides

Answer 4

• Bacteriostatic
  
  • ​Inhibits protein
• Used in upper/lower respiratory tract; skin & soft tissue infections
• Syphillis, gonorrhea, chlamydia (STDs); Lyme disease
• CI= allergy
• S/E: GI r/o especially N/V
  
  • Azithromycin & Clarithromyocin has less GI S/E than others
• Interactions: Highly protein bound & metabolized by liver
  
  • > risk of interactions
• Erythromyocin, Azithromycin, Clarithromycin

Question 5

Quinolones

Answer 5

• Potent bacteriocidal
  
  • ​Destroys bacteria by altering DNA
• Broad spectrum (mostly gram - and some gram +)
  
  • Pseudomonas; pneumococcus; E.coli
• Excreted primarily by kidney as unchanged drug
• Used for: complicated UTI, respiratory, skin, GI, bone & joint infections
• S/E: HA, dizziness, insomnia, nausea, constipation, flatulence, rash; prolonged QT segment
• Interation: Antacid, Ca, Mg, Fe, Zinc
  
  • ​Decreases absorption so take 1 hr before/ after
• Ciprofloxacin (Cipro)

Question 6

Aminoglycosides

Answer 6

• Bacteriocidal
  
  • ​Prevents bacterial synthesis
• Often used in conjection with other antibx
• Very potent; Gram - and some gram +
• Pneumonia, meningitis
• CI: allergy; pregnant women (life threatening only)
• S/E: ototoxicity, nephrotoxicity
• For short term only
• Interactions: other nephrotoxic meds, vanco, cyclosporins, loop diurectics (> ototoxic risk)
• Gentamicin

Question 7

Tetracyclines

Answer 7

• Bacteriostatic
  
  • ​Inhibits protein synthesis
• Gram +/- & Protozoans
  
  • ​Chlamydia; mycoplasma; acne
• Don’t give w/milk, antacids, iron salts = decreased absorption
• Tooth discoloration r/t affinity for Ca
• Don’t use in pregnant or nursing mothers
• S/E: teeth staining; photosensitivity; diarrhea; vaginal infections
• Interaction + > anticoagulant effect
• Tetracycline, Doxycycline
  *

Question 8

Clindamycin

Answer 8

• Semi-synthetic
• Bacteriostatic or bacteriocidal (depending on concentration)
  
  • Inhibits protein synthesis
• Gram + & anaerobic
• Uses: chronic bone infections, GU tract & intra-abdominal infections, septicemia, staphylococci
• CI= Allergy, ulcerative colitis, enteritis
• S/E= GI upset (N/V), abdominal pain, diarrhea, anorexia

Question 9

Vancomycin

Answer 9

• Bacteriocidal
  
  • ​Inhibits cell wall synthesis = death
• Not active against gram -, fungi, yeast
• Used to tx MRSA, colitis
• CI= allergy, renal dysfunction
• S/E: nephrotoxicity, ototoxicity (like aminoglycosides)
  
  • “Redman Syndrome” = flushing & itching of upper body most commonly associated with rapid infusion
    
    • Also decreases BP
• Toxic- so specific drug levels must be monitored with therapy for safety

Question 10

Metronidazole

Answer 10

• Antimicrobial
• Interferes with DNA synthesis (like quinolones)
• Good against anaerobic
• Uses: intra-abdominal & gynecologic infections
• Usually an oral prep
• S/E: dizziness, HA, GI discomfort, nasal congestion
• CI: alcohol (increases intolerance)
• Avoid alcohol 24 hours prior and 36 hours after therapy completion
• Interaction: lithium, benzodiapines, cyclosporins, calcium channel blockers, antidepressants

Question 11

Insulins

Answer 11

• Functions as replacement for endogenous insulin
• Restores ability to metabolize carbos, fats & proteins
  
  • storage of glucose in liver; convert to glycogen to fat stores
• “Bandaid” → doesn’t fix underlying problem
• Used in DMI and DMII
• CI: NKDA; Hypoglycemia
• Alwys test BS prior to administration
• A/E: hypoglycemia (fast & urgent) leading to potential brain damage, shock & death
• Given using “sliding scale”

Question 12

Rapid Insulin

Answer 12

• Onset ~15 min
• Peak 40 min to 60 min
• Duration 24 hours
• Give within 15 minutes of meals
• Humalog (Insulin lispro), Novalog

Question 13

Short Insulin

Answer 13

• Onset ~30 to 60 min
• Peak 2.5 hrs
• Duration 4-6 hours
• Regular insulin
  
  • Humulin R, Novolin R

Question 14

Intermediate Insulin

Answer 14

• Onset 2-4 hrs
• Peak 4-8 hr
• Duration 16-20 hr
• Cloudy appearance
• NPH (insulin isophane)

Question 15

Long Insulin

Answer 15

• Onset 1-2 hr
• Peak 3-9 hr or continous
• Duration 24 hours
• Lantus (insulin glargine)

Question 16

Meglitinides

Answer 16

• Oral anti-diabetics
• Glinides
• Increase release of insulin from pancreatic beta cells
• Fast acting with short duration
• Taken before each meal
• Pandin, Starlix

Question 17

Thiazolidinediones

Answer 17

• Oral anti-diabetics
• Regulates genes involved in glucose & lipid metabolism
• Insulin sensitizing
• CI: heart failure (may exacerbate)
• A/E: peripheral edema, wt. gain
• Actos, Avandia

Question 18

Sulfonylureas

Answer 18

• Oral anti-diabetic medication
• Oldest group
• Binds to receptors of beta cells of pancrease to stimulate release of insulin
  
  • Secondary = decrease glucagon secretion
• Not used in DMI
  
  • Used in early stage DMI
• A/E: wt gain (r/t insulin secretion), skin rash, nausea, heartburn
• Glipizide (Glucatrol)
• Onset = rapid ~1 hour
• Peak 1-3 hours
• Duration 6-8 hours