HealthInfo Waitaha Canterbury
Biologics (TNF inhibitors)
Biological therapies include tumour necrosis factor (TNF) inhibitors. They are used to treat certain types of autoimmune conditions when standard treatments have been unsuccessful.
Autoimmune conditions are conditions in which your body's defence system (immune system) attacks healthy tissues. They include:
- rheumatoid arthritis and psoriatic arthritis (both also known as inflammatory arthritis)
- bowel conditions such as Crohn's disease
- skin conditions such as chronic plaque psoriasis.
TNF inhibitors block natural inflammatory substances in your body called tumour necrosis factor alpha. This helps to decrease swelling and weakens your immune system, thereby slowing or stopping damage from the condition. TNF inhibitors include as adalimumab, etanercept and infliximab.
TNF inhibitors are given by injection. You take adalimumab and etanercept by injecting it into your skin, usually into your thigh or stomach. You have to go to a day ward to get infliximab, where you get it via an IV drip into your vein.
Testing and monitoring
TNF inhibitors can have serious side effects including an increased risk of infection. Before prescribing a TNF inhibitor, your doctor may test for infections. This may include tests for tuberculosis (TB), hepatitis and chickenpox.
They will also review your immunisation record to make sure you have received all vaccinations recommended on the New Zealand Immunisation Schedule. You may need to catch up if you have missed any.
You must avoid live vaccinations if you are receiving a TNF inhibitor. These include varicella (chickenpox) vaccine, tuberculosis (BCG) and measles, mumps and rubella (MMR). The following vaccines are safe to take:
- hepatitis A vaccine and hepatitis B vaccine
- influenza vaccine
- vaccine against pneumococcal infection
- HPV (human papillomavirus) vaccine.
While you are receiving a TNF inhibitor, your doctor will also order blood tests regularly to monitor its safety and how well it is working.
Side effects and increased risk of infection
TNF inhibitors can cause side effects, although not everyone gets them. They include bruising, redness and tenderness at the injection site. If this happens:
- change the site for each injection into the skin
- tell your doctor or phone Healthline 0800-611-116.
Because they weaken your immune system, TNF inhibitors have been associated with an increased risk of infections. These may be mild, such as a cold. Or they may be more severe, such as septicaemia (infection of your blood).
Contact your doctor immediately or phone Healthline 0800-611-116 if you develop:
- signs of infection such as a high temperature, an ongoing cough, weight loss, sore throat or feeling weak, tired and unwell
- signs of an allergic reaction such as muscle or joint pain, fever, rash, intense itching, swelling of your face or hands, sore throat, headache and difficulty swallowing.
Written by HealthInfo clinical advisers. Page created July 2024.
SourcesReview key: HIMIA-48768
