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Risks and drawbacks

Women discussing trials

This page tells you about possible drawbacks to taking part in a clinical trial. There is information about


Possible risks

There will be some risk that an experimental treatment could harm you. The research team may not know a great deal about the new treatment yet. They will keep a close eye on you, and will stop the treatment if necessary.

Remember - even in phase 1 or 2 trials, the treatment has been carefully researched in the laboratory before it is given to patients. With phase 3 trials, more is known about the new treatment so there is less risk that there could be a harmful side effect.


Side effects

There is a chance you will get side effects that you (and your doctor) were not expecting. If you are in a phase 1 trial, the researchers may not be able to tell you much about side effects. You will be told everything they do know before you agree to take part in the trial.

You will be asked to report all your side effects to your doctor or nurse. You may be asked to keep a diary at home or fill in questionnaires about side effects such as feeling sick or tiredness.


Other possible drawbacks

There are other drawbacks. You may have to make more trips to hospital and find this increases your worry about cancer. You may also have to do some paperwork.

If you need more check ups and tests, you will spend more time at the hospital. This will cost you time and money. If you don't like visiting hospitals, you may need to think carefully about this.

You can ask if there is money available to cover your fares. Trials can go on for a long time and fares can add up.

For some people, more check ups means more reassurance. For others, it means more worry. Only you know how these appointments are likely to affect you.


Can I leave the trial?

You can withdraw from a trial at any point. You don't have to give a reason. If you withdraw, you can have the standard treatment available for your type and stage of cancer. Withdrawing from a trial will not be held against you in any way.

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Updated: 10 October 2013