BNF CHAPTER 1 - GASTROINTESTINAL Flashcards
Give examples of aminoglycosides (GN), and what types of bacteria it works on.
Gentamicin + Neomycin. They work on mainly gram-negative bacteria. Has a poor effect on anaerobic bacteria
When are aminoglycosides mainly used ?
They are given via injection and are used in blind therapy of undiagnosed serious infections. it is usually given in conjunction with metronidazole
what are the dosing instructions for aminoglycosides
Loading dose and maintenance dose is based on the patient’s ideal body weight. it is usually given OD and this provides adequate serum concentrations
Higher doses are recommended for immunocompromised, serious infections and neonates
Whenever possible the treatment should not exceed 7 days.
Contraindications for aminoglycosides
gentamicin should not be given with furosemide due risk of nephrotoxicity (kidneys) and ototoxicity (ear).
it should be avoided during pregnancy
give examples of carbapenems and what types of bacterias it works on
Imipenum and Meropenum work on psuedomonas aeruginosa
it is a broad spectrum antibiotic
when would you use a carbapenems
suspected sepsis, severe hospital-acquired infections, hospital-acquired pneumonia, Complicated UTI, abdominal infections, skin + soft tissue infections
what are the two special things about imipenem and ertapenem
ertapenem is not active aganist pseumonomas aerugosina
imipenem needs to be co-administered with cilastatin (enzyme inhibitor) because it is partially metabolized by renal enzymes.
the other carbapenems are stable in the kidneys
give examples of cephalosporins and the types of bacteria it works on
cefotaxime , cefalexin , ceftriaxone
it is a broad-spectrum antibiotic and it is used to treat complicated UTI and infections of the CNS
give examples of the indications of cephalosporins ?
first generation (cefalexin) and second-generation (cefaclor) are useful in complicated UTI or UTI in pregnancy
give examples of the dosing instructions for cephalosporins.
ceftriaxone has a long half-life and therefore administered OD
Cefuroxime axetil is poorly absorbed and needs to be administered with food
cefalexin can be taken during pregnancy - dosing QDS
contraindications for cephalosporins
interacts with warfarin- increases the anticoagulant effect
Give examples of macrolides and which types of bacterias it works on
Claire loves mac - broadly (ACE)
azithromycin, erythromycin, clindamycin
it is a broad-spectrum antibiotic.
it has a similar profile to penicillins but it is technically a different class.
common side effects of macrolides
N+V, diarrohea, GI discomfort in some patients.
However this can be avoided by reducing the dose, but if a serious infection is suspected then a higher dose is needed.
Dosing of azithromycin
once daily due to tissue concentrations being high and it has a long half life
contraindications with macrolides
not recommended during pregnancy
interacts with statins, CCB, warfarin (increasing their concentration)
give examples of penicillin and which bacteria it works on.
penicillins are bactericidal and mainly work of gram-positive bacteria.
amoxicillin, phenoxymethylpenicillin , benzylpenicillin
common side effects of penicillins?
nausea, diarrhoea - this can cause colitis, GI discomfort, thrush,
encephalopathy (causes changes to the brain)- this happens with very high doses +/- severe renal impairment
pen v - dosing and indications
QDS a day on an empty stomach
used for tonsilitis, upper respiratory tract infections.
or for continuing treatment after injections of benzylpenicillin
why is pen v not recommended for serious infections?
the absorption of pen v is unpredictable and the plasma concentrations are variable.
However, it is safe in pregnancy and breast-feeding
what is the indication of flucloxacillin
used for penicillin-resistant staph infections and cellulitis
this is because flucloxacillin does not secrete penicillinase.
important side effects of flucloxacillin
cholestatic jaundice
hepatitis
use in caution in hepatically-impaired patients
dosing instructions of flucoxacillin
QDS a day on an empty stomach
it is safe in pregnancy and breastfeeding women
give examples of broad-spectrum antibiotics
ampicillin - used for exacerbations of chronic bronchitis, middle ear infections and UTI’s
co-amoxiclav - used for infections that are likely cause by amoxicillin resistant beta lactamase producing strains
side effects of co-amoxiclav
cholestatic jaundice - it can occur during or shortly after use.
most common in ppl aged 65+ , men.
usually self limiting
dosing of broad-spectrum penicillins + is it safe during pregnancy
they are safe during pregnancy
TDS ( take with or without food)
give examples of tetracyclines, and what type of bacteria does it work against?
it is a broad-spectrum antibiotic, but it is rarely used due to resistance.
examples include tetracycline, doxycycline, and minocycline
remember like this - tdm goes in cycles
important MHRA alert with tetracyclines
can be deposited in growing bones,
can stain teeth yellow - tetracycline + doxycycline
therefore not recommended in children aged 12 and under
cannot be used in pregnancy or breastfeeding
common interactions with tetracyclines
absorption of this drug is impaired when taken with milk, calcium, magnesium, iron, zinc and antacids (just remember vitamins and minerals )
maciz - magnesium, antacids, calcium and zinc
doxycycline advice
can increase photosensitivity - wear SPF 30 +
caution with muscle weakness
can stain the teeth yellow or grey
minocycline warnings
it is no longer recommended due to its side effects of dizziness and vertigo ( feeling as tho things are spinning around you)
it can cause irreversibe pigmentation
higher risk of lupus erythematosis-like syndrome
give an example of quinolones and the type of bacterias it works against
works against gram-positive and gram-negative.
it is not effective against anaerobes.
examples; ciprofloxacin, ofloxacin and moxifloxacin
MHRA Alerts for quinolones
can induce convulsions for patients with or without a history of convulsions.
taking NSAIDS with this medication can increase the chance of convulsions
caution in pts aged 60 and over due to increased risk of tendon damage
caution in pts taking corticosteroids due to increased risk of tendon damage
can cause arthropathy (disease of the joints) of weight-bearing joints and therefore not recommended in children and growing adults
photosensitivity - wear SPF 30 and above
can cause tendon damage - therefore contraindicated in pts with a history of tendon damage
should not be taken during pregnancy
remember it like this - quinolone makes the joints hurt
dosing and administration instructions for quinolones
ciprofloxacin should not be given with milk, calcium, iron , zinc, or magnesium
ciprofloxacin is given BD
AVOID IN PREGNANCY
give examples of glycopeptides and what type of bacteria does it work against.
works against aerobic and anaerobic bacteria
it is given by injection
Vancomycin , Teicoplanin - remember it like this glycopeptides watch TV.
Glycopeptides indication and dosage
vancomycin and teicoplanin can be given orally for the treatment of C.difficile infection (this is the only situation that it can be given orally - due to the poor absorption profile when given orally).
plasma concentration must be monitored throughout therapy.
should be avoided during pregnancy
main side effect of glycopeptides
ototoxicity and nephrotoxicity
tazocin - indication and dosing
it consists of tazobactam and piperacillin.
broad-spectrum antibiotic and it works against anaerobes.
used for sepsis, hospital-acquired pneumonia
and other complicated infections.
avoid in pregnancy
given by injection
antibiotics cautionary and advisory label
Space doses evenly throughout the day and keep taking this medicine until course is finished, unless told to stop.
G.I side effects= N&V, Superinfection (Clindamycin and broad spectrum kill normal flora and allow selective organisms to thrive so can cause C.diff or Thrush (Candida)
amoebic infection - definition
it is a gastrointestinal illness caused by a parasite, which is spread through human poop
(anaerobic infection)
what are the drugs of choice in an amoebic infection? (giardiasis)
mepacrine hydrochloride 100mg TDS for 7 days
or metronidazole 1g TDS for 3 days, 1g BD for 4 days (total is 7 days treatment )
antibacterial considerations before supplying
- viral infections should not be treated with antibiotics
- avoid blind prescribing, always take a culture sample
- generally narrow spectrum antibiotics are preferred.
- the dose of the antibiotic should be based on factors such as age, weight, hepatic function, renal function and severity of the infection, allergy, pregnancy, current medication regimie,
- avoid prolonged therapy and always complete the antibiotic course
- follow national and local guidelines.
- review antibiotic if sensitivity occurs.
give examples of notifiable diseases
anthrax
botulism
mumps and rubella
cholera
COVID-19
diarrhoea (if bloody and infectious)
plague
paratyphoid fever
SARS
Scarlet fever
smallpox
tetanus
tuberculosis
typhus
whooping cough
yellow fever
BNF page 541
what is the management of early sepsis or high risk of sepsis
give broadspectrum antibiotic at the highest dose (immediately - within 1 hour).
samples and blood cultures should be taken to the lab to be tested.
once the causative microbe has been identified treat as per local and national guidelines.
the need for vasodilators, inotropes, intravenous fluids and oxygen should be assessed and given without delay - taking into consideration of their systolic BP and lactate concentration.
pts should be monitored no later than every 30 minutes
which antibiotic is given as a prevention of reoccurrence of rheumatic fever
phenoxymethyl penicillin or sulfadiazine
what antibiotic do you give for the PREVENTION invasive group A streptococcal infection
Pen V
if the patient is allergic than give erythromycin or azithroymycin
What antibiotic do you give for the PREVENTION of secondary cases of meningococcal meningitis?
ciprofloxacin or rifampicin
what antibiotics do you give for the PREVENTION of secondary cases of haemophillus type b infection
close contacts of the index case such as - ppl in the household, pre-school or primary school setting should recieve treatment.
First choice - rifampicin
alternative includes ceftriaxone
treatment lasts up to 4 weeks
what antibiotics do you give for the PREVENTION of secondary cases of haemophillus type b infection
close contacts of the index case such as - ppl in the household, pre-school or primary school setting should recieve treatment.
First choice - rifampicin
alternative includes ceftriaxone
treatment lasts up to 4 weeks
which antibiotic is prescribed for the prevention of whooping cough
clarithromycin , azithroymcyin or erythromycin
needs to be given within 3 weeks of onset of cough
what is the antibiotic of choice given for the prevention of pneumococcal infections in sickle-cell patients
pen v
if allergic erythromycin
what is the treatment for COMMUNITY-acquired septicaemia
a broad spectrum antipseudomonal penicillin -
TAZOCIN (piperacillin and tazobactam) with TIMETIN (ticarcillin with clavulanic acid)
or
broad spectrum antibiotic - cephlasporins - cefuroxime
if an anaerobic infection is suspected add metronidazole
if meticillin resistant stap.aureus infection suspected add vancomycin
what is the treatment for HOSPITAL -acquired septicemia
a broad spectrum antipseudomonal penicillin -
TAZOCIN (piperacillin and tazobactam) with TIMETIN (ticarcillin with clavulanic acid) with ceftazidme , imipenem with cistatin or meropenem.
if an anaerobic infection is suspected add metronidazole
if meticillin resistant stap.aureus infection suspected add vancomycin
Cardiovascular infections - endocarditis (native valve) caused by staphylococci
give flucoxacillin for 4 weeks,
(if you suspect a lung abscess give for at least 6 weeks)
GENERAL RULE OF THUMB
Staphylococci infection - flucoxacillin
streptococci - benzylpenicillin or pen v
MRSA - vancomycin
Anaerobic infections - metronidazole
pseudonomas - gentamicin
meningitis initial empirical therapy
benzylpenicillin should be given before going to hospital as long as this does not delay the trip to the hospital.
3 months - 50 years old - if the causing agent has not been identified whilst in hospital - give cefotaxime or ceftriaxone.
Diabetic foot infection - course of action
first choice - oral flucloxacillin 500mg to 1g QDS for 7 days for a mild infection
penicillin allergy - clarithromycin (500mg BD) or erythromycin (500mg QDS)
for moderate to severe - based on clinical assessment. IV flucloxacillin with or without gentamicin and or metronidazole / co-amoxiclav
what is the treatment therapy for otitis media?
amoxicillin for 5- 7 days
penicillin allergy - clarithromycin
pregnancy - erythromycin
give paracetamol or ibuprofen for the pain
this is caused by inflammation (infection) of the middle ear
what is the treatment of otitis externa
first line - give paracetamol for pain relief, and use a warm flannel
second line - topical acetic acid 2% (1 spray TDS) for 7 days or topical antibiotic (neomycin ) 3 drops TDS
if you suspect cellulitis - flucoxacillin 250mg QDS
What treatment do you give for conjunctivitis?
first-line - clean eyelids with cotton wool dipped in warm water. use a warm compress on the affected eye
it is usually self-limiting
second line - chloramphenicol eye drops - instill one drop into the eye every 2 hours for the first 48 hours, then frequency to 3-4 times daily
chloramphenicol ointment - apply 3-4 times daily .
what treatment do you give for typhoid fever
cefotaxime
what treatment is given for an acute sore throat
first line - paracetamol or ibuprofen for pain.
FEVERPAIN score above 2 - treat with antibiotics
2nd line - phenoxymethylpenicillin 500mg QDS or 1g BD ( for 5-10 days)
give clarithromycin 250mg to 500mg QDS for 5 days
what treatment do you give for influenza?
annual vaccination is essential for those deemed high-risk.
at-risk patients receive anti-viral medication oseltamivir 75mg BD for 5 days.
at-risk patients
- pregnant
- COPD
- CVD disease
- Renal disease
- Liver disease
what treatment do you give for sinusitis?
- paracetamol and ibuprofen for pain relief
- if symptoms last less than 10 days - no antibiotics
- symptoms last for more than 10 days - consider high-dose nasal corticosteroids if they are aged 12 and over.
- if systemically unwell or at high risk of complications then give antibiotics.
phenoxymethylpenicillin 500g QDS - 5 days
penicillin allergy - clarithromycin 500mg BD - 5 days OR erythromycin 250-500mg QDS - 5 days
treatment of acute exacerbation of COPD
amoxicillin 500mg TDS or doxycycline 200mg on day 1 then 100mg - total duration is 5 days.
penicillin allergy - clarithromycin 500mg BD for 5 days
scarlet fever - treatment
1st choice - phenoxymethylpenicillin 500mg QDS for 10 days
penicillin allergy - clarithromycin 250-500mg BD for 5 days
