Granisetron is an anti-sickness medicine.
The most common side-effects are constipation and headache.
|Type of medicine||5HT3-receptor antagonist anti-sickness medicine|
|Used for||Prevention or treatment of sickness associated with chemotherapy, radiotherapy or surgery in adults|
|Also called||Kytril®; Sancuso®|
|Available as||Tablets, patches, and injection|
Granisetron is known as a 5HT3-receptor antagonist. It is prescribed to stop you from feeling sick. It works by blocking the effect of a naturally produced chemical in your body, called serotonin. Serotonin is also referred to as 5HT.
Chemotherapy, radiotherapy and surgery may all cause the release of an increased amount of serotonin in your body. There are small receptors in your small intestine and brain called 5HT3 receptors. Serotonin acts on these receptors and causes you to feel sick. Granisetron works by blocking serotonin from acting on the 5HT3 receptors, and this stops you from feeling (or being) sick.
Before taking granisetron
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 granisetron it is important that your doctor knows:
- If you are pregnant or breast-feeding.
- If you have been told you have an irregular heartbeat.
- If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, such as herbal and complementary medicines.
- If you have ever had an allergic reaction to a medicine.
How to take granisetron
- Before you start this treatment, read the manufacturer's printed information leaflet from inside your pack. The manufacturer's leaflet will give you more information about granisetron and a full list of the side-effects which you may experience from taking it.
- Take granisetron exactly as your doctor tells you to. The way you are told to take the tablets will depend upon the reason you are taking them. If you are due to have a chemotherapy or radiotherapy treatment that could cause you to feel sick, your doctor will prescribe you a dose of granisetron about an hour before the treatment. You will then be asked to continue to take granisetron tablets during the course of treatment - it is usual to be prescribed 2 mg daily for up to seven days. If you are being prescribed granisetron because you are due to have an operation, you will be given one dose shortly before the surgery, and then prescribed another dose to take afterwards if needed. If you are unsure about which is right for you, ask your doctor, nurse, or pharmacist for advice.
- Swallow the tablets whole with a drink of water. It is not important whether you take them before or after eating food.
- If you forget to take a dose, take it as soon as you remember. If it is nearly time to take your next dose when you remember, skip the missed dose and take your next dose when it is due. Do not take two doses together to make up for a forgotten dose.
- If you need an anti-sickness medicine for a few days because of chemotherapy and you are unable to take tablets, you may be prescribed a skin patch to use as an alternative. Your doctor will tell you how to use the patch, but as a guide, you should apply the patch at least 24 hours before the treatment is due to start and leave it in place until at least 24 hours after your treatment has finished. The patch is applied to your outer arm and can be worn for up to seven days. You can wash and bathe as normal while you are wearing the patch, but you should not allow the patch to be in direct contact with bright sunlight or heat (such as an electric blanket or a hot water bottle).
Getting the most from your treatment
- Even if you do not feel like eating or drinking, try to sip water regularly to prevent you from becoming dehydrated.
- Rather than trying to eat three main meals a day, try eating small, simple but nourishing snacks, every few hours.
Can granisetron 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 granisetron. 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 granisetron side-effects ||What can I do if I experience this?|
|Constipation||Try to eat a well-balanced diet, and drink several glasses of water each day|
|Headache||Ask your doctor to prescribe/recommend a suitable painkiller|
|Sleeping problems||This should soon pass|
|Diarrhoea, abdominal pain||Drink plenty of water, and if troublesome, speak with your doctor|
If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.
How to store granisetron
- Keep all medicines out of the reach and sight of children.
- Store in a cool, dry place, away from direct heat and light.
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.
If you are having an operation or any dental treatment, tell the person carrying out the treatment which medicines you are taking.
If you buy any medicines, check with a pharmacist that they are suitable to take with your other medicines.
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.
Further reading & references
- Manufacturer's PIL, Kytril® Tablets 1 mg and 2 mg; Roche Products Limited, The electronic Medicines Compendium. Dated July 2011.
- Manufacturer's PIL, Sancuso® 3.1 mg/24 hours transdermal patch; ProStrakan, The electronic Medicines Compendium. Dated July 2013.
- British National Formulary; 66th Edition (September 2013) British Medical Association and Royal Pharmaceutical Society of Great Britain, London
Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. EMIS has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.
Dr Helen Huins