Updated February 2023

What is sulfasalazine?

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Sulfasalazine is a medication used to treat certain childhood rheumatic conditions (diseases which may affect joints, muscles, skin or eyes). This can include juvenile arthritis (JIA) and inflammatory bowel disease.

It is a medication that works by suppressing your immune system. It reduces the damage done by inflammation, rather than just reducing pain. Because of this, it is called a disease modifying antirheumatic drug (DMARD). Other medications in this group include leflunomide, methotrexate and hydroxychloroquine.


Important things to remember

  • You must see your rheumatologist regularly to make sure the treatment is working and check for possible side effects.
  • You should have regular blood tests as suggested by your rheumatologist.
  • If you are worried about any side effects, you should contact your rheumatologist as soon as possible.
  • If you stop sulfasalazine for any reason, you must contact your rheumatologist.

How will it help?

Sulfasalazine is a medication that works slowly. You can expect your child to gradually start feeling better, but it might take one to three months.

How is sulfasalazine given?

Sulfasalazine is usually given as a tablet. There are two types of tablets available: plain and enteric coated. The enteric coated should not be crushed, as these tablets have a special coating which makes them more gentle on the stomach.

What is the dose and how often is it given?

Treatment starts slowly: usually one tablet a day. This is increased over a few weeks. The dose is adjusted to your child’s weight.

How long will it be used for?

Sulfasalazine can be continued long-term to maintain disease control.

Are there any side effects?

Sulfasalazine is usually effective, however as with all medications, side effects can occur. Some are common, and some are rare. Most people don’t have any problems when they take sulfasalazine.


Most common side effects


Nausea (feeling sick) vomiting, loss of appetite & diarrhoea

  • Lowering the dose

Orange coloured urine and tears

  • There is no need for treatment. However, don’t wear contact lenses, as they may become stained.


  • Paracetamol

Sulfur allergy (Itchy skin rash)

Skin rash / sun sensitivity

  • Stop medication, see your doctor
  • Use high factor sunscreen and hats

Mouth ulcers Sore gums Sore throat

  • Notify your doctor

Rare side effects


Disturbance in the blood counts (change in blood tests results)

Upset liver function

  • Usually returns to normal if sulfasalazine dose reduced or stopped

Lowered sperm count in males

  • Usually returns to normal if sulfasalazine dose reduced or stopped

Mood changes

  • Notify your doctor

Allergic reactions and severe skin reactions

  • Stop medication and urgently notify your doctor

Things you need to know when your child is taking this medication

All children taking sulfasalazine should be seen regularly by their paediatric rheumatologist to help monitor their health and minimise side effects.

What to do if your child is sick
It is safe to give sulfasalazine if your child is sick with a mild cold or cough. Don’t give sulfasalazine if your child:

  • Has had vomiting/diarrhoea  
  • Is sick and you’re not sure why.

If you’re not sure, talk to your doctor and get them checked if necessary before giving mycophenolate.

Sulfasalazine can interact with other medications. Talk to your doctor before taking any prescription medications, natural medications and medications that you can buy over the counter.

Sulfalasazine is safe with all immunisations. Children should follow the standard immunisation schedule.

There is no increased risk of infections for children on sulfasalazine.

Sulfasalazine and alcohol are both broken down by the liver. Drinking alcohol while you are on this medication can put extra strain on the liver. It is not known how much is safe, so it is suggested that anyone on sulfasalazine should avoid drinking alcohol.

Sexual health and pregnancy 
Sulfasalazine has been safely used in women who are pregnant and breastfeeding. Having been on sulfasalazine in the past does not change the chances of having babies later. Sulfasalazine can decrease the sperm counts in males, but this usually goes back to normal once the medication is stopped.

Myths and misconceptions
You may hear a lot of different information about sulfasalazine from friends, pharmacists or people that you know. If you are worried about anything, please talk to your child’s doctor or nurse for more information. If your child is taking sulfasalazine they should see their paediatric rheumatologist regularly to make sure the treatment is working and to minimise any possible side effects.