There are different types of drugs used to control sickness (nausea and vomiting) in cancer care.
Over the past 20 years, the drugs used for cancer sickness have improved. These drugs are often called anti emetics.
There are many different types of anti sickness medicines. Your doctor decides which drugs to give you based on whether your sickness is caused by your cancer or its treatment, and your past medical history.
How anti sickness drugs work
Anti sickness drugs work by either:
- blocking the vomiting centre in the brain
- blocking receptors in your gut that trigger nausea in the brain
- acting directly on your stomach by increasing the rate at which it empties and moves food into your bowel
Different types of anti sickness drugs
There are lots of different types of drugs doctors use for sickness. Some are tablets, capsules or liquid.
Some are injected into a vein, or a muscle, or just under the skin. A useful way of taking anti sickness medicine is through a syringe pump if you are being sick a lot. The pump can give continuous tiny amounts of a drug.
Metoclopramide works by blocking the vomiting centre. It also acts directly on the wall of the gut. It encourages the stomach to empty its contents into your bowel.
Metoclopramide helps to get rid of the heavy feeling that you can have when you feel sick.
You can have metoclopramide as:
- a tablet
- a liquid
- an injection
You usually take it for up to 5 days.
Prochlorperazine belongs to the group of widely used drugs called phenothiazines. Phenothiazines drugs act by blocking the vomiting centre in the brain.
You can have prochlorperazine:
- as a tablet
- as an injection into the muscle
- a tablet that dissolves when you put it between your gum and upper lip
Other drugs in the phenothiazine group include:
- chlorpromazine - this tends to make you drowsy so it's used less often
Domperidone is like metoclopramide, it speeds up the emptying of your stomach. It also acts on a part of your brain called the chemoreceptor trigger zone. It works well for sickness from various causes.
You usually take domperidone for up to a week.
These drugs block receptors in the gut and brain that send messages to the chemoreceptor trigger zone and the vomiting centre. They are also called 5HT3 blockers.
Serotonin blockers work very well for some types of sickness. They work best when you have steroids at the same time.
There are several drugs in this group, including:
- ondansetron (Zofran)
- granisetron (Kytril)
- palonosetron (Aloxi)
These drugs come as tablets or injections. Ondansetron is also available as a tablet that melts on your tongue. Granisetron also comes as a patch you put on your skin.
Some anti anxiety drugs can reduce sickness. Lorazepam (Ativan) is the drug from this group that doctors most often use for chemotherapy sickness. You usually have it with other types of anti sickness drugs.
You might have lorazepam to help treat anticipatory nausea and vomiting. In this case, you might take it the evening before and the morning of your chemotherapy.
Cyclizine is an antihistamine that doctors often use for sickness.
It dissolves easily and mixes safely with other drugs in a syringe pump. This can help people who find swallowing difficult for any reason.
Steroids can help to control sickness. They can help particularly with sickness from:
- increased pressure in the skull (from a brain tumour or secondary cancer in the brain)
- a blockage in the gut
- some types of chemotherapy (when used with other anti sickness drugs)
Steroids reduce swelling so they can help to lower pressure in the skull, which causes sickness.
They might reduce swelling around a tumour blocking the gut and help to allow fluids to pass through. This relieves the vomiting that a bowel obstruction can cause. Steroids will only work for a limited time. But they might help until you have other treatment. Or, they can help to make you more comfortable.
Dexamethasone is a steroid that you could have as an injection into a vein just before chemotherapy. You might have steroid tablets to take at home for a couple of days after chemotherapy.
Dexamethasone can cause difficulty with sleeping and so it’s better if you take it before lunchtime.
Blockages in the gut might mean you have drugs to reduce the amount of liquid in your intestines. These drugs encourage the body to reabsorb fluids from the digestive system. This reduces the build up of fluid above the blockage. You won't feel so sick or need to be sick as often if there is less of a build up.
Buscopan (hyoscine butylbromide) reduces fluid in the intestines and is an anti spasm (cramps) drug. It helps to reduce cramps by relaxing the smooth muscle in the bowel and slowing down the movement of the bowel.
Octreotide (Sandostatin) can help to relieve the sickness you get from a blockage in the gut by reducing the amount of liquid produced in the bowel.
Nabilone is a drug developed from cannabis (marijuana). It is licensed for treating severe sickness from chemotherapy that is not controlled by other anti sickness drugs.
It works very well for some people, but can cause drowsiness or dizziness in others. These side effects can last for a couple of days after you've stopped taking it.
Aprepitant (Emend) is a newer drug which works by blocking a substance in the body called neurokinin. You might have it with steroids and serotonin blockers to help control sickness caused by cisplatin based chemotherapy.
You take a tablet one hour before chemotherapy and then one tablet a day for the next 2 days.
Fosaprepitant (Ivemend) is a similar drug to aprepitant. It’s only available as an injection into the bloodstream through a cannula. It is also used for sickness caused by cisplatin based chemotherapy.
Sedatives can help to control sickness. Some anti psychotic medicines such as levomepromazine (Nozinan) can also help to control sickness but may make you drowsy unless they are used at a low dose. This can be a helpful effect if you take them at night.
Haloperidol (Haldol) is another sedative that is particularly good for sickness due to medicines. So, doctors often use it for sickness related to morphine. It is also used for sickness related to:
- high blood calcium levels (hypercalcaemia)
- kidney or liver failure
- a blocked bowel