Penicillins

Question 1

Give some examples

Answer 1

Amoxicillin

Co-amoxiclav (Amoxicilin & calvulinic acid trade name Augmentin)

Question 2

What are the indications for use

Answer 2

• Empirical Tx pneumonia (strep pneumonia, H-influenza)
• UTI (E. coli)
• Combo Tx for hospital acquired infection/intra-abdominal sepsis
  (gram -ve, anaerobes, antibiotic resistant)
• Combo Tx for H. pylori associated peptic ulcers

Question 3

What are the mechanism of action

Answer 3

• Inhibit enzymes responsible for cross-linking peptidoglycans in bacterial cell wall (weakened)
• Prevents maintenance of osmotic gradient –> cell swelling, lysis & death
• Penicillins contain B-lactam ring

Question 4

What are the side effects

Answer 4

• Abx ass colitis (can be complicated with perforation/ death)
• Skin rash
• Allergy/anaphylaxis (hypotension, angioedema, bronchospasm)
• Cholestatic jaundice (Co-amoxiclav)

Question 5

What are the contra-indications

Answer 5

• Hx Penicillin allergy
• Reduction in severe renal impairment (risk of crystalluria)
• Caution in people at risk of C.Diff infection

Question 6

What are the interactions

Answer 6

• Methotrexate (increased risk toxicity)

- Enhance coagulative effect of warfarin by killing normal gut flora that synth Vit K

Question 7

What are some administration details

Answer 7

Iv to oral switch after 48hrs