Medicines for Crohn's disease

Key points about Crohn's disease medicines

  • If you have Crohn’s disease, lifestyle changes and medicines can be used to control the inflammation in your gut and to reduce your body’s immune response.
  • The treatment chosen depends on your symptoms and how bad they are.
  • More than 1 medicine may be needed and some need to be taken regularly to stop symptoms from flaring up.
  • Find out how to take medicines for Crohn’s disease safely and possible side effects.
blue unaunahi tile generic
Print this page

To manage Crohn's disease, medicines can be used to keep you symptom-free or stop the disease from getting worse. Medicines for Crohn’s can work by stopping or controlling the inflammation in your gut and preventing your body’s immune system from attacking itself.

The kind of treatment depends on the type of symptoms and how bad they are. Often medicines are prescribed in ‘steps’, depending on your symptoms, how bad they are, and your body’s response. 

Some medicines are only used for a short time when your symptoms flare up and other medicines are taken long-term to keep your Crohn’s disease under control. It's important to keep taking these medicines regularly if you want to stop symptoms from flaring up.

The main groups of medicines to treat inflammation in Crohn’s disease are:

  • steroids 
  • immunosuppressants 
  • biologics (TNF inhibitors)
  • antibiotics and vitamin supplements.

  • Steroids are used to treat a flare-up of your symptoms and are usually used for a short time until your flare-up has settled.
  • They work by reducing the activity of immune cells that cause inflammation.
  • Steroids are preferred for people who are newly diagnosed or who have no more than 1 flare-up per year.
  • Steroids are mainly given as a course of prednisone tablets over a few weeks. The dose is reduced gradually and then stopped once your symptoms ease. A course of steroids for a few weeks is normally safe.
  • Budesonide tablets or capsules may be used for mild to moderate Crohn's disease affecting the part of your gut called the ileum or the ascending colon.
  • A steroid enema (hydrocortisone) may also be used for a mild flare-up in the lower large intestine. The enema is used to get the medicine directly to the place it's most needed. This reduces the chances of side-effects in the rest of your body.  
  • Steroid injections may be needed for a severe flare-up.

  • Immunosuppressants are usually started when your symptoms continue and haven’t responded to other treatments.
  • Sometimes they're started after surgery to make sure you stay in remission, without flare-ups.
  • These medicines reduce the inflammation in your gut by suppressing your immune system.
  • Immunosuppressants take time to work. It can take up to 2 or 3 months before you feel better.
  • You'll need regular blood tests to check your blood cells, liver, and kidney function while you're taking them.
  • Examples of immunosuppressants for Crohn’s disease are azathioprine and mercaptopurine.

Biologics and biosimilar medicines are used to treat moderate to severe Crohn's disease for people who fit 1 of these categories:

    • Have a fistula.
    • Haven't found other medicines effective enough.
    • Have problems tolerating other medicines they’ve tried.
    • Have stopped responding well to other medicines.

TNF inhibitors

  • These medicines reduce inflammation by binding to a protein called tumour necrosis factor-alpha (TNFa). Your body’s immune system makes TNFa and normally keeps the level of TNFa steady, but in Crohn’s disease you make too much TNFa which leads to inflammation.
  • These medicines may be needed for several months or years as a long-term treatment to help stop symptoms from coming back.
  • TNF inhibitors are given either as injections under the skin with pre-filled syringes, or as a slow injection into a vein in your arm (called an intravenous infusion) by a doctor or nurse.
  • In Aotearoa New Zealand TNF inhibitors are funded if you qualify for them. A specialist needs to apply for this for you.
  • Examples include:

Interleukin inhibitors

  • These medicines reduce inflammation by binding to proteins called interleukins. Interleukins are made by your immune system and by blocking specific interleukins, it stops your body attacking itself.
  • An example is ustekinumab (Stelara®)

Integrin inhibitors

  • These medicines reduce inflammation by binding to proteins called integrins. Integrins are found on certain white blood cells and increase inflammation.
  • An example is vedolizumab (Entyvio®).

Learn more about biologics and biosimilar medicines.

Other medicines such as antibiotics and vitamin supplements may be prescribed in some situations:


If you have an infection, an abscess, or an infected fistula as a complication of Crohn's disease, you may be prescribed antibiotics (eg, metronidazole or ciprofloxacin).

Vitamin supplements

Vitamins, either injected or in tablet form, may be used to correct nutritional imbalances that can occur because of poor absorption of food and fluid from your bowel.

Free helplines

Healthline logo

Text 1737 Helpline logo

Logo with link to Māori Pharmacists website

Credits: Healthify He Puna Waiora editorial team. Healthify is brought to you by Health Navigator Charitable Trust.

Reviewed by: Angela Lambie, Pharmacist, Auckland

Last reviewed:

Page last updated: