R-DHAP is a cancer drug combination made up of the drugs:

  • R – rituximab (also called Mabthera), a type of targeted cancer drug called a monoclonal antibody
  • DH – dexamethasone, which is a steroid
  • A – cytarabine (also known as Ara C), a chemotherapy drug
  • P – cisplatin, a chemotherapy drug

It is a treatment for high grade non-Hodgkin lymphoma that has come back.

How it works

These cancer drugs destroy quickly dividing cells, such as cancer cells.

How you have it

Cytarabine and cisplatin are colourless fluids that you have into your bloodstream (intravenously). Rituximab is a colourless fluid that you might have into your bloodstream or as an injection under the skin (subcutaneous injection). 

You usually have the steroid drug (dexamethasone) as tablets (orally) but you may also have it into your bloodstream. If you take dexamethasone as tablets, you should swallow them whole after a meal, or with milk, as they can irritate your stomach. It is best to take them early in the day, immediately after breakfast. 

Drugs into your bloodstream

You have the treatment through a drip into your arm or hand. A nurse puts a small tube (a cannula) into one of your veins and connects the drip to it.

You might need a central line. This is a long plastic tube that gives the drugs into a large vein, either in your chest or through a vein in your arm. It stays in while you’re having treatment, which may be for a few months.

An injection under the skin

You usually have injections under the skin (subcutaneous injection) into the stomach, thigh or top of your arm.

You might have stinging or a dull ache for a short time after this type of injection but they don't usually hurt much. The skin in the area may go red and itchy for a while.

Taking your tablets

You must take tablets according to the instructions your doctor or pharmacist gives you.

You should take the right dose, not more or less.

Talk to your specialist or advice line before you stop taking a cancer drug.

When you have R-DHAP

You have R-DHAP as cycles of treatment. Each cycle lasts 3 weeks. You may have 1 or 2 cycles.

You have each cycle in the following way:

Day 1
  • You have dexamethasone tablets or as a drip into your bloodstream.
  • You have rituximab as a slow drip into your bloodstream.
  • You have cisplatin as a drip into your bloodstream for 24 hours.
  • You have hydration fluids as a drip into your bloodstream.
Day 2
  • You have cytarabine as a drip into your bloodstream twice (each drip lasts for 3 hours and you have them 12 hours apart).
  • You have hydration fluids as a drip into your bloodstream.
  • You have dexamethasone tablets or as a drip into your bloodstream.
Day 3 and 4
  • You have dexamethasone tablets or as a drip into your bloodstream.
Day 5 to day 21
  • You have no treatment.

You then start a new treatment cycle.

Your nurse or doctor will give you steroid eye drops to use for 5 to 7 days to help prevent your eyes getting sore.

Allergic reaction

Some people can have an allergic reaction to rituximab so you have the first dose slowly over about 4 hours. To help prevent a reaction you will have paracetamol and a drug called chlorphenamine (Piriton). If you have a reaction your nurse will stop the drip. They will start it again once your symptoms have reduced. You should be able to have further doses of rituximab at a faster rate (about 2 hours).


You have blood tests before and during your treatment. They check your levels of blood cells and other substances in the blood. They also check how well your liver and kidneys are working.

Side effects

How often and how severe the side effects are can vary from person to person. They also depend on what other treatments you're having. For example, your side effects could be worse if you're also having other drugs or radiotherapy.

When to contact your team

Your doctor, nurse or pharmacist will go through the possible side effects. They will monitor you closely during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:

  • you have severe side effects 
  • your side effects aren’t getting any better
  • your side effects are getting worse

Early treatment can help manage side effects better. 

Contact your doctor or nurse immediately if you have signs of infection, including a temperature above 37.5C or below 36C.

We haven't listed all the side effects here. Remember it is very unlikely that you will have all of these side effects, but you might have some of them at the same time.

Common side effects

These side effects happen in more than 10 in 100 people (10%). You might have one or more of them. They include:

Increased risk of infection

Increased risk of getting an infection is due to a drop in white blood cells. Symptoms include a change in temperature, aching muscles, headaches, feeling cold and shivery and generally unwell. You might have other symptoms depending on where the infection is.

Infections can sometimes be life threatening. You should contact your advice line urgently if you think you have an infection. 

Breathlessness and looking pale

You might be breathless and look pale due to a drop in red blood cells. This is called anaemia.

Bruising and bleeding

This is due to a drop in the number of platelets in your blood. These blood cells help the blood to clot when we cut ourselves. You may have nosebleeds or bleeding gums after brushing your teeth. Or you may have lots of tiny red spots or bruises on your arms or legs (known as petechiae).

Changes to how the kidneys work

To help prevent kidney damage, it is important to drink plenty of water. You might also have fluids into your vein before, during and after treatment. You have blood tests before your treatments to check how well your kidneys are working.

Feeling or being sick

Feeling or being sick is usually well controlled with anti sickness medicines. Avoiding fatty or fried foods, eating small meals and snacks, drinking plenty of water, and relaxation techniques can all help.

It is important to take anti sickness medicines as prescribed even if you don’t feel sick. It is easier to prevent sickness rather than treating it once it has started.

Skin changes

You might notice skin changes, such as dryness, itching and rashes similar to acne on your face, neck and trunk. 

Tell your doctor if you have any rashes or itching. Don't go swimming if you have a rash because the chlorine in the water can make it worse.

If your skin gets dry or itchy, using unperfumed moisturising cream may help. Check with your doctor or nurse before using any creams or lotions. Wear a high factor sun block if you’re going out in the sun.

Increased amount of uric acid in the blood

High uric acid levels in the blood are due to the breakdown of tumour cells (tumour lysis syndrome). You will have regular blood tests to check your uric acid levels and may have a tablet called allopurinol to take. Drinking plenty of fluids helps to flush out the excess uric acid.

Occasional side effects

These side effects happen in between 1 and 10 out of every 100 people (1 to 10%). You might have one or more of them. They include:

  • heart changes including changes to the heart rate or a heart attack
  • high or low blood pressure
  • difficulty swallowing
  • sore throat
  • sore mouth and ulcers
  • loss of appetite
  • diarrhoea or constipation
  • changes to your eyesight including blurred vision
  • dry or watery eyes
  • pain - can be in the tummy, ear, neck, back, where the drip goes into the vein or where the cancer is
  • unable to pass urine (urinary retention)
  • ringing in the ears (tinnitus)
  • hives
  • runny nose
  • shivering
  • sweating and night sweats
  • a loss of muscle strength
  • tiredness and weakness
  • an allergic reaction
  • cold syndrome - signs of inflammation such as rash, joint pain and itchiness caused by exposure to the cold
  • mood changes such as suicidal thoughts, irritability, moodiness
  • delusions, hallucinations and schizophrenia becoming worse if you are or have been schizophrenic

Rare side effects

These side effects happen in fewer than 1 in 100 people (1%). You might have one or more of them. They include:

  • a second cancer - this might happen years after the end of treatment
  • loss of hearing
  • swollen tummy (abdomen)
  • problems with how your blood clots
  • swollen lymph nodes
  • taste changes
  • lung changes causing asthma and a decreased amount of oxygen in the blood
  • dark patches on the skin
  • headache
  • tingling, numbness or pain in the fingers and toes
  • chest pain
  • swelling and infection at the drip site
  • decrease of the amount of magnesium in the blood
  • growth of breast tissue in men - can be painful

Coping with side effects

We have more information about side effects and tips on how to cope with them.

What else do I need to know?

Other medications, food and drink

Cancer drugs can interact with some other medicines and herbal products. Tell your doctor or pharmacist about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies.

Pregnancy and contraception

This treatment might harm a baby developing in the womb. It is important not to become pregnant or father a child while you're having treatment and for a year afterwards. Talk to your doctor or nurse about effective contraception before starting treatment.

Loss of fertility

You may not be able to become pregnant or father a child after treatment with these drugs. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.

Men might be able to store sperm before starting treatment. And women might be able to store eggs or ovarian tissue. But these services are not available in every hospital, so you would need to ask your doctor about this.    


Don’t breastfeed during this treatment and for a year afterwards because the drugs may come through in your breast milk. 

Treatment for other conditions

Always tell other doctors, nurses, pharmacists or dentists that you’re having this treatment if you need treatment for anything else, including teeth problems.


Don’t have immunisations with live vaccines while you’re having treatment and for up to 12 months afterwards. The length of time depends on the treatment you are having. Ask your doctor or pharmacist how long you should avoid live vaccinations.

In the UK, live vaccines include rubella, mumps, measles, BCG, yellow fever and one of the shingles vaccines called Zostavax.

You can have:

  • other vaccines, but they might not give you as much protection as usual
  • the flu vaccine (as an injection)
  • the coronavirus (COVID-19) vaccine - talk to your doctor or pharmacist about the best time to have it in relation to your cancer treatment

Members of your household who are aged 5 years or over are also able to have the COVID-19 vaccine. This is to help lower your risk of getting COVID-19 while having cancer treatment and until your immune system Open a glossary item recovers from treatment.

Contact with others who have had immunisations - You can be in contact with other people who have had live vaccines as injections. Avoid close contact with people who have recently had live vaccines taken by mouth (oral vaccines) such as the oral typhoid vaccine.

If your immune system is severely weakened, you should avoid contact with children who have had the flu vaccine as a nasal spray as this is a live vaccine. This is for 2 weeks following their vaccination.

Babies have the live rotavirus vaccine. The virus is in the baby’s poo for about 2 weeks and could make you ill if your immunity is low. Get someone else to change their nappies during this time if you can. If this isn't possible, wash your hands well after changing their nappy.

More information about this treatment

For further information about this treatment go to the electronic Medicines Compendium (eMC) website.

You can report any side effect you have to the Medicines Health and Regulatory Authority (MHRA) as part of their Yellow Card Scheme.

This page is due for review. We will update this as soon as possible.

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