Aminosalicylates

Question 1

State the common indications for mesalazine

Answer 1

1) First-line in the treatment of mild-moderate ulcerative colitis
↳ Sulfasalazine is an alternative but has largely been replaced by mesalazine for this indication.

Question 2

State the common indications for sulfasalazine

Answer 2

1) Treatment of acute attack of mild to moderate and severe UC, Active crohns disease. Also used in maintenance of UC
2) management of rheumatoid arthritis, in which it is used as a disease-modifying antirheumatic drug (DMARD), usually as part of combination therapy.

Question 3

Outline the MoA of aminosalicylates

Answer 3

Exert their therapeutic effects by releasing 5-aminosalicylic acid (5-ASA). This has both antiinflammatory and immunosuppressive effects, and appears to act topically on the gut rather than systemically. For this reason, 5-ASA preparations are designed to delay delivery of the active ingredient to the colon.

Question 4

outline the Important side effects cause by mesalazine and sulfasalazine

Answer 4

1) Common- GI upset (nausea, dyspepsia) and; headache
2) Can cause rare but serious blood abnormalities (e.g. leucopenia, thrombocytopenia)
3) Renal impairment.
4) In men, sulfasalazine may induce a reversible decrease in the number of sperm (oligospermia). It can also cause a serious hypersensitivity reaction, comprising fever, rash and liver abnormalities.

Question 5

one side effect of aminosalicylates in general is blood dyscrasia. Explain how this should be managed

(Dyscrasia -a disease or disorder, especially of the blood)

Answer 5

A blood count should be preformed and the drug stopped immediately if there is suspicion of a blood dyscrasia

Question 6

what should be monitored in general during treatment with an aminosalicylates and how often should this be done?

Answer 6

Renal function should be monitored before starting an oral aminosalicylate, at 3 months of treatment and then annually during treatment
↳ In renal impairment, monitor more frequently

Question 7

patients who are allergic or hypersensitive to which class of drugs, should avoid amonisalicylates?

Answer 7

Salicylate hypersensitivity (e.g. aspirin)

Question 8

what are the important interactions to be aware of when prescribing aminosalicylates?

Answer 8

Mesalazine tablets with a pH-sensitive coating (e.g. Asacol® MR) may interact with drugs that alter gut pH. For example, PPIs increase gastric pH and so may cause the coating to be broken down prematurely. Lactulose lowers stool pH and may prevent 5-ASA release in the colon.

Question 9

What counselling advice should be given to those prescribed aminosalicylates?

Answer 9

Blood disorders: report any unexpected bleeding, bruising, purpura, sore throat, fever or malaise during treatment

Question 10

1) Mesalazine is available in numerous different preparations e.g. Asicol, Pentasa, Octasa, is any one oral preparation more effective than the other?
2) if it is necessary to switch between brands, what are patients advised to do?

Answer 10

1) No evidence to show than any one oral preparation is more effective than the other
2) if switching between brands of mesalazine, report any changes in symptoms

Question 11

can mesalazine be used in breastfeeding?

Answer 11

Diarrhoea reported in breast-fed infants, but negligible amounts of mesalazine detected in breast milk. Monitor infant for diarrhoea

Question 12

what two things should be monitored in those taking sulfasalazine?

Answer 12

1) Blood disorders: FBC is neecessary initially and then at monthly intervals for the first 3 months
2) Liver function: At monthly intervals for the first 3 months

Question 13

what additional patient and carer advice should be given to individuals taking sulfasalazine?

Answer 13

1) some soft contact lenses may be stained

2) may discolor urine - Harmless

Question 14

what should be monitored in those taking mesalazine

Answer 14

For safety, renal function should be checked in patients receiving oral mesalazine. Avoid if eGFR <20mL/min