Biological and Immune Suppressant Therapies Explained! How they work, risks, etc...

As an IBD sufferer, I have been on many treatments over the last 15 years, I take them, often without fully understanding what they are and what they can do for me. Now facing a new biological therapy I had many questions such as; why is is different? how does it work? what are the risks of having an impaired immune system?

I started researching all the therapies I know and am now sharing my findings with you, Hopefully this will also allow carers and loved ones the understanding of the risks we face so they can help us to stay healthy, as well as eliminate avoidable problems.

Your immune system, which normally responds to foreign threats, microorganisms, and intestinal bacteria, is out of balance and mounts inflammatory attacks against your own body. It is believed that substances in the intestines are mistaken for invading substances.

The immune system causes temporary inflammation to combat these substances and lessens the response as you regain your health.

In IBD, the inflammation can persist long after the time when the immune system should have completed its response. This in effect means the body starts attacking itself, thus causing a flare up of disease.

For the majority of IBD sufferers a flare up is treated successfully with course of medications such as corticosteroids (often Prednisolone) and 5-ASA Such as Mesalazine.

All the following have an impact on the bodies immune system and can leave patients vulnerable to illness, disease, infection and in some cases, serious development of otherwise ‘normal’ ailments.

So what are they and how do they work?

Corticosteroids (Commonly used Prednisolone)

Corticosteroids are anti-inflammatories, meaning they decrease levels of inflammation in the body. They are man-made versions of the hormone cortisol which is created by the human body in the adrenal glands. Taking corticosteroids causes the body to slow down production of, or stop making, cortisol. The body then receives the cortisol it needs from the corticosteroids.


5-ASA drugs (such as Mesalazine/Olsalazine ) are bowel specific anti-inflammatory drugs. They belong to a group of medicines that act on the inflamed lining of the gut (intestine) to prevent the formation of substances that cause inflammation. They have less systemic absorption and fewer adverse effects than many other medications mentioned.

IBD is also treated with various other oral immune suppressant drugs such as Azathioprine.


In autoimmune diseases, Azathioprine reduces the immune system attack on normal tissues and so reduces the severity of the symptoms, and in many cases halts the progress of the disease. However, the immune system relies on the action of different types of white blood cells that are produced in the bone marrow and lymph glands. Azathioprine works by decreasing the production of these white blood cells.

Unfortunately, white blood cells also fight invading germs, so during treatment the body becomes more susceptible to infections. It can cause anaemia and reduced production of platelets can cause problems with blood clotting.

I was on all the above at various times over the last 15 years, However, Azathioprine, which did manage my symptoms well for 11 years, was thought to raise the risk of