DRUGS FOR INFLAMMATORY BOWEL DISEASE
AMINOSALICYLATES (5-ASA)
Included in this group of drugs are : Sulphasalazine, Mesalazine, Olsalazine and
Balsalazide. Comment of mode of action is required ?
Route of administration :
Oral as tablets, granules and suspensions (sulphasalazine only).
Rectally as suppositories or enemas.
Cautions / Contraindications :
Sulphasalazine :
Glucose 6 phosphate dehydrogenase deficiency – may cause haemolysis.
Pregnancy / breast feeding :
Sulphasalazine may be associated with transient reversible oligospermia in men of child
bearing potential.
Folic acid supplements should be prescribed to those trying to conceive and during
pregnancy.
Small amounts of the drug are excreted in breast milk although this is not thought to be a
risk to healthy infants.
Contraindicated in patients with hypersensitivity to sulphonamides / co-trimoxazole.
All 5-ASA’s
Use with caution in patients with renal impairment – and discuss with Nephrology team
& monitor renal function regularly whilst on treatment.
Avoid in patients with severe renal failure.
There is a possible increased risk of haematological toxicity (leucopenia, unexplained
bleeding / bruising and purpura) when patients are taking azathioprine or 6 –
Mercaptopurine – monitor blood tests more frequently.
British Society of Gastroenterology (BSG) recommended monitoring schedule :
BSG Guidelines :
Pre-treatment assessment
Monitoring
FBC, U&E, Creatinine, LFT’s
FBC & LFT’s at 1 month
FBC, U&E, Creatinine, LFT’s at 3
months
If results stable repeat above blood
tests about once yearly
Following dose changes
Consider repeating bloods 1 month
after increase
Actions to be taken :
Nausea, dizziness, headache, worsening
diarrhoea
Severe abdominal pain
If troublesome, reduce or stop treatment
and consider alternative
Monitor carefully – if WBC continues to
fall, withhold until discussed with
Gastroenterology specialist team
Monitor carefully – if neutrophil count
continues to fall, withhold until discussed
with Gastroenterology specialist team
Monitor carefully – if platelet count
continues to fall, withhold until discussed
with Gastroenterology specialist team
Check amylase level; consider ultrasound
or CT scanning
> 2 fold rise above upper limit of normal
reference range for ALT / AST
Withold until discussed with specialist
team; Ultrasound liver.
Rise of creatinine level above the normal
range (or rise of > 20% compared to
baseline)
Withold until discussed with specialist
team; Urinalysis for proteinuria etc; renal
ultrasound; nephrology opinion.
Check FBC immediately and withhold
until result available. discuss with
Gastroenterology specialist team
Withold; seek urgent specialist
(preferably Dermatological) advice
WBC < 4.0 x 109/l
Neutrophils < 2.0 x 109/l
Platelets < 150 fl
Abnormal bruising or severe sore throat
Unexplained acute widespread rash
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reactions re-evaluated on the basis of suspected adverse reaction reports to the
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risk of renal disease : a large British epidemiological study. Gastroenterology
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