Penicillins- narrow spectrum

Question 1

What is it indicated for?

Answer 1

Benzylpenicillin/phenoxymethylpenicillin- tonsillitis, pneumonia and enocarditis and meningitis

Flucloxacillin- skin, soft tissue, bone and joint infections, otitis externa and endocarditis

Question 2

What is the spectrum of activity?

Answer 2

Active against gram-positive organisms

Question 3

How do they work?

Answer 3

inhibit enzymes responsible for cross-linking peptidoglycans of the bacteria cell wall

Question 4

What are the side effects of these drugs?

Answer 4

Minor GI upset
Allergy
Neurological toxicity- convulsions and coma at high doses or toxic accumulation n renal failure
Flucloxacillin rarely causes liver toxicity

Question 5

What are the warnings of these drugs?

Answer 5

Dose reduction in severe renal impairment

Contraindicated in allergy to any penicillin

Question 6

What interactions occur with these drugs?

Answer 6

All penicillins reduce renal excretion of ▲ methotrexate, increasing the risk of toxicity.

Question 7

What are the names of some of the drugs in this class?

Answer 7

flucloxacillin, benzylpenicillin, phenoxymethylpenicillin