antibiotics Flashcards
what is the interaction between trimethoprim + methotrexate
increased risk of nephrotoxicity and methotrexates side effects
which antibiotic has high activity against anaerobic bacteria
metronidazole
what is the interaction between ciprofloxacin + theophylline
Ciprofloxacin interacts with theophylline- increases exposure by altering the rate of metabolism of theophylline.
Moderate interaction -manufacture advises monitor + adjust dose
should phenoxymethylpenicillin be taken with food or without
Phenoxymethylpenicillin- take on an empty stomach
what should be avoided 2 hours before/after taking doxycycline
indigestion remedies/iron/zinc 2 hours before or after
what are the counselling points for doxycycline
- full glass of water
- protect skin from sunlight
- no indigestion remedies/iron/zinc 2 hours before or after
should flucloxacillin be taken with food or without food
Flucloxacillin should be taken on an empty stomach
which antibiotic should not be routinely used in children under 12 due to deposition in growing bones + teeth
doxycycline
which antibiotic may impair the performance of skilled tasks e.g driving
ciprofloxacin
which antibiotic is used for antibiotic-associated colitis (pseudomembranous colitis)
vancomycin
which antibiotic class is associated with tendon rupture
quinolones e.g ciprofloxacin, ofloxacin, levofloxacin
why should you avoid using Gentamicin in patients with renal impairment
because gentamicin is excreted by the kidneys. Renal impairment can cause accumulation- increased risk of nephrotoxicity + ototoxicity
note: if you must use it, reduce or increase the dose according to impairment
what colour can rifamipicin change your urine to
urine colour can be change anywhere from:
yellow - reddish/orange - reddish/brown
what colour can nitrofurantoin change your urine to
dark yellow to brownish
what symptoms should patients taking Trimethoprim recognise + report
seek immediate medical attention if symptoms such as fever, sore throat, rash, mouth ulcers, purpura, bruising or bleeding develop
note: these are signs of blood disorders
which medication interact with quinolones + increase the risk of seizures
quinolones e.g ciprofloxacin, ofloxacin, levofloxacin
- ibuprofen
- naproxen
- indometacin
- theophylline
which antibiotics are most likely to cause a c.difficile infection
- Clindamycin
- cephalosporins (cefalexin, cefradine, cefadroxil, cefaclor)
- fluoroquinolones (Ciprofloxacin, Moxifloxacin, Levofloxacin, Ofloxacin)
- broad-spectrum penicillins
what is the first line treatment for c.difficle
first line: vancomycin
second line: Fidaxomicin
which antibiotic class is not suitable to children and why
tetrayclines: e.g doxycycline, tetracyline, Tigecycline
it causes deposits in growing bone and teeth, by binding to calcium, causes staining and occasionally dental hypoplasia
which antibiotic is contraindicated in patients with jaundice or hepatic dysfunction
co-amoxiclav
co-amoxiclav can cause jaundice + reduce hepatic function
describe the monitoring around vancomycin
- All patients require serum-vancomycin measurement (on the second day of treatment, immediately before the next dose if renal function normal, earlier if renal impairment—consult product literature)
- The next vancomycin dose should not be withheld whilst awaiting results unless toxicity is suspected
- Administration rate should not exceed 10mg/min to reduce the risk of red-man’s syndrome.
what is the interaction between amoxicillin + methotrexate
Amoxicillin is predicted to increase the risk of toxicity when given with methotrexate. Manufacturer advises
monitor.
what is the first line treatment for community acquired pneumonia
first line= amoxicillin
alternative if penicillin allergic: clarithromycin, doxycycline, or erythromycin (in pregnancy)
note: this is for both low + moderate severity
which antibiotic is commonly used as an alternative for penicillin allergy in pregnant/breastfeeding women
erythromycin
what is the antibiotic regimen for a h-pylori infection
Oral first line for 7 days: - A proton pump inhibitor (twice daily) - amoxicillin (1 g twice daily) and either - clarithromycin (500 mg twice daily) or - metronidazole (400 mg twice daily)
note: if penicillin allergy: just give PPI + Clarithromycin + Metronidazole
what is the interaction between clarithromycin + atorvastatin
Clarithromycin increases the exposure to Atorvastatin - severe
what is the interaction between clarithromycin + amlodipine
Clarithromycin increases the exposure to Amlodipine
which food should not be taken with ciprofloxacin
avoid dairy products and mineral-fortified drinks with oral ciprofloxacin- reduces exposure of ciprofloxacin
which antibiotic is used to treat meningitis
Benzylpenicillin
what is the treatment for acute sinusitis
first line: phenoxymethylpenicillin, if severe or high risk co-amoxiclav
- if penicillin allergy: doxycycline or clarithromycin (erythromycin in pregnancy)
- note: acute sinusitis is usually viral + self limiting. antibiotics only used if the patient has had no improvement in symptoms after trying nasal corticosteroids*
which antibiotic do you give to a pregnant woman if she has a UTI but is it at term in her pregnancy
cefalexin
note: nitrofurantoin is given if pregnant but not at term. nitrofurantoin should avoid at term (36-42 week)—may produce neonatal haemolysis. once the pregnant woman is at term, can only give cefalexin
when should you avoid giving nitrofurantoin in pregnant women
can give nitrofurantoin in pregnancy but at term (36-42 weeks in pregnancy)
which antibiotic is contraindicated in patients with G6PD deficiency
nitrofurantoin
note: G6PD is an enzyme that supports the functioning of red blood cells. Individuals with this deficiency are susceptible to haemolytic anaemia
which class of antibiotics are potent enzyme inhibitors
Macrolides e.g Clarithromycin, erythromycin, azithromycin
which antibiotic is used to treat meningitis if the person is allergic to penicillin
cefotaxime
note: first line is normally benzylpenicllin
can chloramphenicol eye drops containing borax or boric acid buffers be used in children younger than 2 years
yes- it is safe to use them
which antibiotic can cause ‘neonatal grey-baby syndrome’
chloramphenicol
why should pregnant women avoid chloramphenicol in the 3rd trimester
because it can cause ‘neonatal grey-baby syndrome’
note: this is chloramphenicol drops/ iv + oral use
what is the treatment for otitis externa
first line: Flucloxacillin
- penicillin allergy: Clarithromycin (or azithromycin or erythromycin).
If pseudomonas suspected: Ciprofloxacin
what is the treatment for otitis media
first line: amoxicillin. if worsening: co-amoxiclav
penicillin allergy: clarithromycin or erythromycin
note otitis media can be viral, bacterial or both
which antibiotics are used in the “initial blind therapy” of endocarditis
- amoxicillin/ ampicillin + low dose gentamicin
penicillin allergy/sepsis: vancomycin + dose dose gentamicin
note: in endocarditis, gentamicin (‘peak’) serum concentration should be 3–5 mg/litre; pre-dose (‘trough’) concentration should be less than 1 mg/litre
which antibiotics should be used for Patients with a human or an animal bite
first line: co-amoxiclav
penicillin allergy: doxycycline + metronidazole
which tablets, when taken with quinolones, further increase the risk of tendon damage
- the risk of tendon damage is increased by the concomitant use of corticosteroids
quionolones e.g ciprofloxacin, Ofloxacin, Levofloxacin, Moxifloxacin
