Infliximab
What is Infliximab?
Infliximab is a targeted disease modifying anti-rheumatic drug (DMARD) that is used to reduce inflammation produced by the body. In certain diseases the immune system is over active, this can target healthy tissues such as joints. Infliximab works on the inflammatory pathway to inhibit proteins called tumour necrosis factors or TNF, reducing the symptoms you get from arthritis such as pain and joint swelling and reduces the chance of further damage to the joints.
Infliximab is known as an anti-TNF biological from its effects, there are other medications in this group such as adalimumab or etanercept.
What is Infliximab used for?
Infliximab is used for the treatments of inflammatory diseases such as:
How is it taken?
Infliximab is taken as an injection into the vein through a drip. This is called a intravenous infusion and is usually given in the rheumatology day unit. It takes around 2 hours to given and you will be monitored throughout and for 1-2 hours after this to make sure you have not developed and side effects.
Medications to prevent a reaction to the drip are given at the same time; these include steroids, paracetamol and anti-histamines.
It is initially given slowly, however if you are managing well it can be given quicker after the 4thdose. This will usually take around an hour in total.
The dose is calculated from your weight and it is given as a loading treatment initially, with infusions at 0, 2 and 6 weeks, it is then given every 8 weeks whilst you remain on the medication.
Infliximab can be given alongside other DMARDs such as methotrexate, or taken on its own.
The infusions can take up to 12 weeks to have an effect. You will require bloods to be taken regularly every 3 months; these can be taken at the day unit. If you are on other medication, you must still attend for blood monitoring for them.
Side effects
There are a few possible side effects that can occur in a small number of people that take infliximab, these include:
- Feeling sick, vomiting and headaches
- These usually settle after taking the infusions for a few weeks.
- Increased risk of infections
- As infliximab dampens the immune system, you can be more prone to infection. You should be seen by your GP if you feel unwell in case you need antibiotics. You must temporarily stop your infusions whilst you are unwell and receiving treatment, they can be started up again when you feel well.
- You should try to avoid contact with others that have chicken pox or shingles.
- Infusion reactions
- Sometimes people can have a reaction whilst receiving the drip, this is reduced by the pre medications that are given. Your observations including blood pressure and pulse are regularly checked.
- If you have a severe reaction, no further infliximab will be given.
- Small increased risk of non-malignant skin cancer
- Anti-TNF treatments have been associated with a small increased risk; you should try to reduce your risk by being safe in the sun and assessing your moles regularly.
- Drug induced lupus
- Rarely infliximab can cause a rash, joint pains and fevers. If this occurs it usually stops after stopping the injections.
Cautions of use
Interactions with other medications
- Your doctor will check if there are any medications that could interact. You can carry on taking your usual painkillers including NSAIDs.
Contraindications of other conditions
- Before starting any biological therapy, your bloods will be checked for infections that can become active again when the immune system is suppressed, this includes hepatitis B, C and HIV. A blood and chest X-ray is taken to exclude previous TB exposure. If you are found to have had previous TB exposure you may need to start preventative antibiotics for a short period before the infliximab is commenced.
- Infliximab is not safe to be used if you are being investigated for or have been diagnosed with cancer.
- Infliximab is not used if you or a close family member have been diagnosed with multiple sclerosis (MS).
- If you have severe lung and heart conditions, anti-TNF treatments may not be suitable.
Operations
- Infliximab should be withheld for 9 weeks prior to surgery (eg. 1 week after your last dose would have been due).
During pregnancy and breastfeeding
- Infliximab is safe for use during the first 16 weeks of pregnancy.
- It is safe to take during breastfeeding.
- There is some evidence to suggest it is safe to be used by the male partner during conception and during their partner’s pregnancy.
Alcohol
- Alcohol and infliximab do not interact, however it is recommended to take alcohol within moderation, following the guidelines of less than 14 units weekly.
Vaccinations
- Flu and the pneumonia vaccines are safe and recommended whilst taking infliximab.
- Live vaccines including the shingles vaccine should not be given due to the dampening down of the immune system.
Useful Links
Versus Arthritis: http://www.versusarthritis.org