Sulfasalazine
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Taken as enteric-coated tablets, swallowed whole with food. Start low and build up over a few weeks to reduce stomach upset. It works slowly, over about 3 months. It can turn urine or skin an orange-yellow colour, which is harmless.
- Rheumatoid arthritis and psoriatic arthritis: Built up to about 1 g (two tablets) twice a day; sometimes increased to 1.5 g twice a day.
It usually takes about 3 months to work.
Tests while you take it
You will have blood tests for your blood counts and liver, more often in the first few months. Tell your team about sore throat, fever, unusual bruising, rash, or yellowing of the skin or eyes.
What to know
Common side effects
The most common effects are feeling sick, headache, and a rash, often early on and often settling with time or a slower dose build-up. Sulfasalazine can turn urine and tears a harmless orange colour, which can stain soft contact lenses. Less often it affects the blood counts or the liver.
Tests and monitoring
You will have blood tests to check your blood counts, liver, and kidney function, before you start and then during treatment. They are more frequent in the first few months (about every 2 to 4 weeks) and usually spaced to about every 3 months once your dose is steady.
Important cautions
Tell your team if you have an allergy to sulfa medicines or aspirin, or a condition called G6PD deficiency. In men, sulfasalazine can lower the sperm count while taking it, which reverses after stopping. Reproductive-health guidance is covered separately.
What to watch for
- A fever, sore throat, or unusual bruising or bleeding, which can point to a low blood count.
- A widespread or blistering rash, which should be checked promptly.
- Yellowing of the skin or eyes.