What is sulfasalazine and how is it used?

Sulfasalazine is a type of drug known as adisease-modifying anti-rheumatic drug (DMARD). It may be used on its own or with other drugs.

Sulfasalazine changes the way your condition affects you, and reduces inflammation, pain and swelling in your joints. It can be used to treat:

If you’re an adult, sulfasalazine can be prescribed by your GP or aconsultant rheumatologist. For children, sulfasalazine should only be started by a specialist.

Sulfasalazine won’t start to work immediately, and it could be at least 12 weeks before you notice any effects.

You shouldn’t take sulfasalazine if you’re known to have an allergy to salicylates. Salicylate is a natural chemical that is found in some foods. It is also the chemical that is in aspirin. You also shouldn’t take sulfasalazine if you are allergic to antibiotics known as sulphonamides.

How is it taken?

Sulfasalazine is generally prescribed as Salazopyrin EN-Tabs. These tablets are specially coated, so that they do not dissolve quickly in your stomach. They should be swallowed whole with a glass of water, not crushed or chewed.

Your doctor will advise you on the correct dose to take. You’ll usually start on a low dose, which is increased gradually over a period of about four weeks.

The dose may be changed, depending on how bad your symptoms are.

Because it’s a long-term treatment, it is important to keep taking sulfasalazine:

  • even if it does not seem to be working at first
  • even when your symptoms start to improve, to help control your condition.

However, you may need to stop this medication if you experience severe side effects.

Side-effects and risks

The most common side effects of sulfasalazine are:

  • feeling sick
  • diarrhoea
  • stomach pain
  • dizziness
  • headaches
  • rashes.

这些副作用通常在第一次发生three months of treatment and often clear up if the dose is lowered. You may be able to increase the dose again after a while if your reaction to sulfasalazine improves and it’s helping your symptoms.

Sulfasalazine may make you more likely to develop infections and allergies. You should tell your doctor orrheumatology teamstraight away if you develop any of the following after starting sulfasalazine:

  • a sore throat
  • a fever
  • unexplained bruising
  • ringing in your ears (tinnitus)
  • any other new symptoms, or anything else that concerns you.

Sulfasalazine may cause your urine to change colour, to orange, but this is nothing to worry about. It may also stain soft contact lenses and tears yellow.

Your doctor will arrange for you to have a blood test before you start treatment. You will then need to have regular checks and blood tests while you’re taking sulfasalazine.

You may be asked to keep a record of your blood test results in a booklet, which you should take with you when you visit your GP or hospital.

Tips to reduce your risk of infection

  • Try to avoid close contact with people you know have an infection.
  • Wash your hands regularly and carry around a small bottle of antibacterial hand gel.
  • Keep your mouth clean by brushing your teeth regularly.
  • Stop smoking if you’re a smoker.
  • Make sure your food is stored and prepared properly.
  • Try to keep your house clean and hygienic, especially the kitchen, bathrooms and toilets.


Check with your doctor before starting any new medication and remember to mention you are on sulfasalazine if you’re treated by anyone other than your usual healthcare team.

You can carry on takingnon-steroidal anti-inflammatory drugs (NSAIDs)orpainkillersif needed, unless your doctor says otherwise. If sulfasalazine works for you, you may be able to reduce your NSAIDs or painkillers after a while.

You shouldn’t take over-the-counter medicines or herbal remedies without talking to your doctor,rheumatology teamor pharmacist first.


It's usually fine for people on sulfasalazine to have vaccinations, but check with your GP andrheumatology teamto make sure a vaccine is safe.

Pneumococcal (new-mow-cock-all) vaccine, which protects against the most common cause of pneumonia (new-mow-nee-uh), and yearly flu vaccines are safe and recommended.

Having an operation

If you’re planning to have surgery, speak to your doctor,rheumatology teamand surgeon about taking your medication. You’ll usually be able to carry on with sulfasalazine, but in some cases, it will need to be stopped for a while before your operation.


There’s no particular reason to avoid alcohol while on sulfasalazine. However, it’s recommended that people try to keep well within the recommended limits for alcohol.

This limit is 14 units a week for women and men. You can find out more about units of alcohol

Fertility, pregnancy and breastfeeding

Guidelines state that it's safe for women to continue using sulfasalazine when trying for a baby and during pregnancy. It's often recommended that you continue sulfasalazine throughout pregnancy to prevent flare-ups.

If you’re pregnant and taking sulfasalazine, you should also take folic acid tablets. This is because sulfasalazine can reduce levels of folic acid in the body.

Talk to your doctor as soon as possible if you are planning a family, or if you become pregnant while taking sulfasalazine.

Sulfasalazine is considered safe to use while you are breastfeeding, unless the baby is premature or at risk of jaundice. Speak to yourrheumatology teamabout this if you have any concerns.

Sulfasalazine can cause a fall in sperm count, but must not be relied upon for contraception. This effect is reversed if treatment is stopped.

Current guidelines say that it’s not necessary for men to stop taking sulfasalazine before trying to father a child. However, if have been trying for a baby for a year or more while on sulfasalazine, you should discuss this with your doctor and arrange to see a fertility specialist to rule out other issues.