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Sirolimus to prevent organ rejection


Sirolimus will be prescribed for you by a specialist doctor.

It is usual to take sirolimus once daily.

It is important that you take all your doses in the same way with respect to mealtimes. So, always take your doses before a meal, or always take your doses after a meal.

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About sirolimus

Type of medicine

An immunosuppressant

Used for

To prevent organ rejection following a kidney transplant operation

Also called


Available as

Tablets and oral solution

Your body can try to reject new donor tissue following organ transplants. Sirolimus helps to prevent this by suppressing your body's immune or defence system.

Your body produces white blood cells called lymphocytes to fight infection or foreign substances which have entered the body. Following a kidney transplant, your body's immune system recognises the new organ as 'foreign' to you and will try to attack it with certain lymphocytes. Sirolimus works by preventing the activation of these lymphocytes and this helps prevent rejection of the transplanted kidney.

Before taking sirolimus

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking sirolimus it is important that your doctor knows:

  • If you are pregnant, trying for a baby, or breastfeeding.

  • If you have any problems with the way your liver works.

  • If you have an infection, or if you have been told you have cancer.

  • If you have ever had an allergic reaction to a medicine.

  • If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.

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How to take sirolimus

  • Before you start this treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about sirolimus and will provide you with a full list of side-effects which you may experience from taking it.

  • Your doctor will prescribe a dose which is tailored to you - it will depend upon the results of your blood tests. It is usual to take sirolimus once daily. Your doctor will tell you what time of day to take your dose, as this could depend upon other medicines you are taking. For example, if you are also taking a medicine called ciclosporin, you will be asked to take your dose of sirolimus four hours after taking ciclosporin. The dose will be printed on the label of the pack to remind you what the doctor said - make sure you take it exactly as you have been told.

  • Although it is not important whether you take your doses before or after food, it is important that you take all your doses in the same way with respect to mealtimes. This is because food can affect how much of the medicine gets into your bloodstream. So, always take sirolimus before a meal, or always take your doses after a meal.

  • Swallow the tablets whole with a drink of water.

  • If you have been given the oral solution, measure out your dose using a dose syringe provided and then add it into a glass of water or orange juice. You should add it to at least 60 ml of water/orange juice. Make sure you drink all of it, and then add a further 120 ml of water/juice to your glass and drink this too so that you get the full dose. Do not mix it with any drinks other than water or orange juice. If you are unsure about how to measure out your dose using the dosing syringe, ask a doctor or pharmacist to show you.

  • If you forget to take a dose at your usual time, take it as soon as you can (but remember about always taking sirolimus before a meal or always taking it after a meal, and taking it four hours apart from a dose of ciclosporin). If when you remember, your next dose is almost due then take the dose that is due but leave out the forgotten dose. Do not take two doses together to make up for a missed one.

  • Your doctor will tell you how long your treatment is expected to continue. Keep taking sirolimus until your doctor tells you otherwise.

Getting the most from your treatment

  • Do not drink grapefruit juice while you are on sirolimus. This is because a chemical in grapefruit juice increases the amount of sirolimus in your bloodstream. This makes side-effects more likely.

  • Try to keep your regular appointments with your doctor. Your doctor will want you to have blood and urine tests during this treatment to check on your progress.

  • While you are taking sirolimus, and for a while after you stop treatment, do not have any immunisations (vaccinations) without talking with your doctor first. Sirolimus lowers your body's resistance and there is a risk that you may get an infection from the vaccine. Also, some vaccines can be less effective.

  • Your doctor will have discussed with you the possibility of a slightly increased risk of cancer (particularly skin cancer) associated with immunosuppressants like sirolimus. Do not use sunbeds, and avoid strong sunlight or use a sun cream with a high sun protection factor (SPF of at least 15).

  • If you buy any medicines or herbal remedies, check with your doctor or a pharmacist that they are suitable for you to take.

  • If you have diabetes mellitus this medicine may affect your blood sugar levels. Test your blood regularly and report any extreme changes to your doctor.

  • You should avoid becoming pregnant while you are taking sirolimus and for at least 12 weeks after stopping it. Make sure you have discussed with your doctor which types of contraception are suitable for you and your partner.

  • If you are having an operation or any dental treatment, tell the person carrying out the treatment that you are taking an immunosuppressive medicine.

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Can sirolimus cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the most common ones associated with sirolimus. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.

Common sirolimus side-effects

(some of these can affect more than 1 in 10 people)

What can I do if I experience this?

Headache, aches and pains

Drink plenty of water and ask a pharmacist to recommend a suitable painkiller. If the aches continue, let your doctor know

Stomach upset (feeling sick (nausea), constipation, diarrhoea)

Stick to simple meals - avoid spicy foods

Skin problems, swollen feet or ankles, menstrual problems, sore mouth, nosebleeds, fast heartbeat, being prone to infections

If any of these become troublesome, discuss them with your doctor

Changes to blood test results

Your doctor will monitor for these

If you experience any other symptoms which you think may be due to the medicine, speak with your doctor or pharmacist for further advice.

How to store sirolimus

  • Keep all medicines out of the reach and sight of children.

  • Store tablets in a cool, dry place, away from direct heat and light.

  • Store Rapamune® Oral Solution in the fridge. Once a bottle has been opened it will keep for 30 days in a fridge - after this time, make sure you have a fresh supply. If necessary, you can leave the solution out of the fridge for a short period of time - but this should be no longer than 24 hours.

Important information about all medicines

Important information about all medicines

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

Report side effects to a medicine or vaccine

If you experience side effects, you can report them online through the Yellow Card website.

Further reading and references

Article History

The information on this page is written and peer reviewed by qualified clinicians.

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