Sounds like 'sull-fuh-SAL-uh-zeen'

Easy-to-read medicine information about sulfasalazine – what it is, how to take sulfasalazine safely and possible side effects.

Type of medicine Also called
  • Aminosalicylate
  • Belongs to a class of medicines known as disease-modifying antirheumatic drugs (DMARDs)
  • Sulphasalazine
  • Salazopyrin®
  • Salazopyrin EN®

What is sulfasalazine?

Sulfasalazine is used to treat a many conditions such as rheumatoid arthritis, ulcerative colitis and Crohn's disease. It works by reducing the inflammation and pain related to these conditions. Sulfasalazine does not cure these conditions. In rheumatoid arthritis, sulfasalazine helps to reduce pain, stiffness and swelling of the joints and reduces damage to the joints. Read more about rheumatoid arthritis. In inflammatory bowel disease such as ulcerative colitis and Crohn's disease, sulfasalazine helps to reduce symptoms such as fever, stomach pain, diarrhoea and rectal bleeding. In New Zealand sulfasalazine is available as tablets (500 mg). 

Watch a video about sulfasalazine for the treatment of arthritis.


  • Ulcerative colitis and Crohn's disease: the usual dose of sulfasalazine is 1 tablet four times a day. Some people may need a lower dose of 1 tablet two times a day.
  • Rheumatoid arthritis: the usual dose of sulfasalazine is 2 tablets 2 times a day. Your doctor will start you on a low dose (1 tablet once a day) and increase your dose slowly over a few weeks. This is so your body can get used to the medicine and reduces side effects.
  • Always take your sulfasalazine exactly as your doctor has told you.
  • The pharmacy label will tell you how much sulfasalazine to take, how often to take it, and any special instructions.

How to take sulfasalazine

  • Take sulfasalazine at the same times each day, with a full glass of water.
  • You can take sulfasalazine with or after food.
  • The sulfasalazine EN tablets have a special coating so the tablet can pass through the stomach. The tablet must be swallowed whole. Do not break, chew or crush the tablets. Do not take any indigestion remedies within 2 hours of taking these tablets; this will interfere with the coating.
  • Plain sulfasalazine may be crushed.
  • It is important that you drink plenty of water while you are taking sulfasalazine (about 6 glasses a day). This is to avoid any problems with your kidneys.
  • Limit drinking alcohol while you are taking sulfasalazine.
  • If you forget to take your dose, take it as soon as you remember that day, but, if it is nearly time for your next dose, just take the next dose at the right time. Do not take double the dose.
  • Keep taking sulfasalazine every day. It may take 6 to 12 weeks before you notice the full benefits.

Possible side effects

Like all medicines sulfasalazine can cause side effects, but not everyone gets them. Often side effects improve as your body gets used to the new medicine. You will need to have blood tests to make sure it is not affecting your blood or kidneys.

Side effects What should I do?
  • Nausea (feeling sick) or being sick (vomiting)
  • Tummy pain
  • Diarrhoea (runny poo)
  • Headache
  • Dizziness
  • These are quite common when you first start taking sulfasalazine and usually go away with time.
  • Take  sulfasalazine with food
  • Headache
  • Dizziness
  • Sit down for a while until the you feel better.
  • Tell your doctor if troublesome
  • Orange coloured urine (wee) and sweat.
  • Contact lenses may become stained
  • This is not harmful. The stain will wash out of most clothing.
  • Tell your optician; other lenses may be better
  • Signs of problems with your blood cells such as bruising or bleeding easily, ongoing sore throat, mouth ulcers, dizziness and feeling tired and fever.
  • Tell your doctor immediately or ring HealthLine 0800 611 116
  • Allergic reaction including any skin rashes, itching, blisters, peeling skin, swelling of the face, lips, mouth or have problems breathing
  • Tell your doctor immediately or ring HealthLine 0800 611 116


  • Sulfasalazine interacts with many medications and herbal supplements (such as St. John's Wort) so check with your doctor or pharmacist.
  • Do not take any indigestion remedies within two hours (before or after) of taking sulfasalazine.

Learn more

Medsafe Consumer Information Sheets:

Salazopyrin EN

Credits: Sandra Ponen, Pharmacist. Reviewed By: Angela Lambie, Pharmacist, Auckland Last reviewed: 20 Oct 2016