Tacrolimus is a medicine which can be used as a treatment for ulcerative proctitis or colitis that has proved to be resistant to, or needed multiple courses of, steroid therapy. It controls the body’s inflammatory response by targeting the immune system. It works in a similar way to azathioprine, and is usually given to people who have not got any better on azathioprine or mercaptopurine, or had side effects meaning they cannot take it. Tacrolimus has been used in high doses to help prevent rejection of organs in patients undergoing organ transplants, such as kidney transplants. It is normal to expect to be taking tacrolimus for a few months, and perhaps up to at least one year, although this will depend on your response to the tablets.
You should take your tacrolimus tablets twice daily, swallowed whole with a glass of water. It is advisable to take them after meals, as this helps to prevent feelings of nausea. If you forget to take a dose, take it as soon as you remember, unless it is nearly time for your next dose. Do not double up on doses.
It is important not to take your tablets with grapefruit juice as this can affect their efficacy.
Tacrolimus can be taken with other tablets, however it is important you tell your doctor about any tablets that you are taking. This includes any over the counter tablets, or herbal/alternative therapies. If you are planning to have any vaccinations, please discuss this with your nurse or doctor, as some vaccines should be avoided while taking tacrolimus. Your doctor or nurse can advise you on this.
Some people report side effects with tacrolimus. These can include headaches, feelings of nausea, and muscle cramps. If you do pick up a viral infection, such as a cough or cold, it can take longer than usual to get over it.
There are some important major side effects of tacrolimus:
• It may rarely affect the bone marrow, resulting in a reduced white blood cell count. This can make you more prone to infection, so it will be necessary to monitor your white blood cell count quite closely while you are taking tacrolimus. I recommend that you have your blood checked at least every 3 months, and more frequently when you first start the medication.
• Hypertension (high blood pressure) can be an important side effect of tacrolimus. It is important to have regular checks, so that any problems can be identified. If you do develop hypertension, reducing your dose of tacrolimus is usually effective at treating this.
• Renal problems – these are usually reversible, and will be picked up quickly by the blood tests performed to monitor you. Any problems which do develop with the kidneys can be reversed by reducing or stopping the tacrolimus.
These blood tests are usually done at your GP surgery, but can be arranged through WKG. By doing these regular tests, any potential problems can usually be detected and dealt with promptly. In addition, you will need to have your tacrolimus ‘levels’ checked, so that any dose changes needed can be identified (this is a blood test, and is usually done at the same time as your other blood tests).
It is essential to have these blood tests done as directed. It is unsafe to take tacrolimus without having these tests. Sometimes, it is necessary to change your tacrolimus dose.
Please make contact with your GP or WKG if you suffer from any of the following side effects while you are taking tacrolimus: sore throat; high temperature; feeling sick or vomiting. We can arrange for you to have an extra blood test, and advise you about any changes you may need to make to your tacrolimus dose.
As with any medication, special care needs to be taken in women of childbearing age. If you are pregnant, or are planning a pregnancy, it is very important that you inform your doctor, so that you can discuss your treatment with them
In some patients with disease which has been difficult to control with other therapies, tacrolimus is beneficial.