Penicillins Flashcards
What indications does benzylpenicilin have?
Endocarditis and meningitis
What indications does phenoxymethylpenicillin have?
Oral infections and prevention of pneumococcal infection in asplenia or in patients with sickle cell disease
What route of administration does benzylpenicillin need to be given in and why?
Parenterally because it is inactivated by gastric acid.
- do not give intrathecally
What are the cautions and contraindications within the penicillin group?
Avoid in patients with a history of anaphylaxis or rash following penicillin administration.
Avoid flucloxacillin in patients with a history of hepatic dysfunction associated with flucloxacillin.
Pivmecillinam is contraindicated in patients under 3 months and in those with GI obstruction
What are the two main interactions of penicillins
Methotrexate: toxicity
Warfarin: bleeding
What are the directions for use when taking penicillins?
Take on an empty stomach - instead of pivmecillinam which is taken with food.
Amoxicillin can be taken with or without food.
What are the two penicillins very associated with cholestatic jaundice
Flucloxacillin and co-amoxiclav
What is the max duration of co-amoxiclav and why?
14 days because of risk of cholestatic jaundice
What are the risks with flucoloxacillin?
Risk of cholestatic jaundice and hepatitis up to 2 months after stopping fluclox
What penicillins are at a high risk of C.diff
Co-amoxiclav and piperacillin - tazobactum
What is the mode of action of penicillins
Interfer with bacteria cell wall synthesis
Bacteriocidal
What bacteria is it active against?
Gram positive and gram negative
What is the usual dose of phenoxymethypenicillin?
250-500mg QDS or
250mg BD
Depending on indication
What is the usual dose of amoxicillin?
500mg TDS
Whats the usual dose of flucloxacillin
250-500mg QDS
