Summary NSG 251 Exam 2 Drug Study Sheet

Sulfonamide Antibiotics
 Mechanism:
o antimetabolite: inhibits growth by blocking bacterial production of folic acid
o bacteriostatic:
 Uses:
o Broad spectrum
o Gram + and – organisms
o UTIs (concentrates in urine)
o MRSA and community acquired infections
o Prophylaxis for HIV patients
 Adverse effects:
o Delayed rash preceded by fever
o Photosensitivity
o Low RBC, WBC, platelet counts
 Interactions/contraindications:
o Allergy to sulfites
o Avoid in pregnancy and infants
o Many Drug interactions:
 Celecoxib (Celebrex): Never combine the two
 Warfarin: Significant interaction; can cause hemorrhage
 Sulfonylureas: Can cause hypoglycemia
 Dilantin: Causes drug toxicity
 Example Medication(s): sulfamethoxazole-trimethoprim
 Nursing Process:
 obtain baseline CBC
 sunscreen/lip protection/proper clothing/limit exposure to sun/no tanning beds
 use back up method of birth control
 Take with 8oz of water and increase fluids (preferably water) to 2-3 L
 take oral medication with food to minimize nausea
 report rash, bleeding, shortness of breath, abdominal pain, or fever to HCP

,Penicillin (Beta-Lactam Antibiotics)
Mechanism:
 Inhibit cell wall synthesis leading to eventual cell lysis
 bacteriostatic
Uses:
 Gram + Infections
Adverse effects:
 allergic reaction
 suppression of bone marrow: low RBC, WBC, platelets
 Hyperkalemia, hypernatremia
 lethargy, anxiety, depression, seizures
Interactions/contraindications:
 Drug allergy
 Many interactions:
 Aminoglycosides: Positive killing effect when combined with penicillin
 Warfarin: Enhances effect (increased bleeding risk)
 Cephalosporins: cross-reactivity possible
 Decreases effect of oral contraceptives
Example Medication(s): Penicillin G, Penicillin V Potassium (all drugs in class end in “cillin”)
Nursing Process:
 use back up method of birth control
 some penicillin’s contain large amounts of sodium and/or potassium: monitor electrolyte levels
 adjust dosage for patients with renal impairment
 assess patient for asthma, aspirin allergy, and sensitivity to cephalosporins as these are associated with higher risk for
penicillin allergy
 administer oral penicillin with water (NEVER with citrus juice, fruit juice, tomato juice, or soda -which deactivate the
antibiotic)
 administer with a small snack to reduce nausea
Fun Facts:
 Beta-lactam refers to the molecular ring-like structure commonly associated with drugs in this class
 some bacteria produce beta-lactamase enzymes that breakdown the beta-lactam ring causing the antibiotic to lose
effectiveness
 beta-lactamase inhibitor drugs are added making these drugs more resistant against these enzyme producing bacteria
 these drugs exhibit time dependent killing (serum drug level must always be within effective dose range to kill
bacteria)

, Cephalosporin (Beta-Lactam Antibiotics)
Mechanism:
 Inhibit cell wall synthesis leading to eventual cell lysis
 bacteriostatic
Uses:
 Currently 5 generations
 As generations increase they move from gram-postive coverage to being more gram-negative
 Vary in effectiveness against gram +, gram -, and anaerobic coverage
Adverse effects:
 most common include mild diarrhea, abdominal cramps, rash, pruritus
Interactions/contraindications:
 Penicillin: Cross sensitivity (chemically similar)
 Alcohol Use: Interacts with alcohol to produce a disulfiram-like reaction causing stomach cramps, nausea, vomiting,
diaphoresis, pruritus, headache and hypotension
 avoid alcohol up to 72 hours after last dose
 decreased effect of oral contraceptives
 pregnancy category B
Example Medication(s): Cefazolin
Nursing Process:
 use back up method of birth control
 give with food to decrease nausea