Penicillin - Amoxicillin Flashcards
What is amoxicillin used for?
1) Emperical treatment of Pneumonia
2) Emperical treatment of UTI
3) as part of combination treatment (co-amoxiclav) for hospital acquires infection or intra abdo sepsis
4) combination treatment for H.pylori associated peptic ulcers
What gram +ve bacteria and what Gram -ve bacteria could be the cause of pneumonia (for which emperical treatment is amoxicillin)?
Gram +Ve = Streptococcus pneumoniae
Gram -ve = Haemophilus influenzae
How does amoxicillin work?
Amoxicillin is a broad spectrum penicillins.
Penicillins are beta lactams that work by inhibiting peptidoglycan cross linking in cell membranes. This weakens the membrane and causes bacterial cell death via swelling and lysis.
What is co-amoxiclav made up of and what is it also known as ?
Co-amoxiclav aka Augmentin = Amoxicillin + Clavulanic acid.
This increases the spectrum of amoxicillin to include staph aureus and gram negative anaerobes.
What are the side effects of amoxicilline?
1) GI upset (nausea / diarrhoea) - sometimes C.DIFF
2) ALLERGY (skin rash / anaphylaxis)
3) Cholestatic Jaundice (side effect of co-amoxiclav)
What are the alternative treatments for a UTI (other than amoxicillin)?
- trimethoprim
- nitrofurantoin
What antibiotics can be used in penicillin allergy?
- Vancomycin
- Doxycycline
- Clindamycin
- Azithromycin
- Metronidazole
*****AVOID beta lactams —> penicillins, cephalosporin, carbapenams!!! DO NOT GIVE AUGMENTIN!
What are the drug interactions of amoxicillin?
1) Penicillins reduce the renal excretion of methotrexate, increasing the risk of toxicity
2) Warfarins. Broad spec penicillins increase the anticoagulant effect of warfarin by killing the normal gut flora that synthesis vitamin K
How do broad spec penicillins enhance the anticoagulant effect of warfarin?
by killing the normal gut floral that synthesis vitamin K