R-DHAP

R-DHAP is a cancer drug combination. It includes the drugs we list below, next to each drug we have how you pronounce the drug name in brackets.

• R – rituximab (ri-tuk-si-mab)
• DH – dexamethasone (deks-a-meth-a-sone)
• A – cytarabine (sye-ta-ra-bin)
• P – cisplatin (sis-pla-tin)

It is a treatment for high grade non-Hodgkin lymphoma.

How does R-DHAP work?

Rituximab is a type of targeted cancer drug called a monoclonal antibody . It targets a protein called CD20 on the surface of the lymphoma cells. Rituximab sticks to all the CD20 proteins it finds. Then the cells of the immune system pick out the marked cells and kill them.

Cytarabine and cisplatin are types of chemotherapy drugs. These drugs destroy quickly dividing cells, such as cancer cells.

Dexamethasone is a type of steroid. It treats lymphoma by stopping the cancer cells growing and killing them. It may also help you feel less sick during treatment. And help reduce your body’s immune response, to try and prevent an allergic reaction to rituximab.

How do you have R-DHAP?

You have rituximab, cytarabine and cisplatin as a drip into the bloodstream (intravenously).

You take dexamethasone as tablets. You 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. Sometimes you have dexamethasone as a drip into the bloodstream.

Drugs into your bloodstream

You might have treatment through a long plastic tube that goes into a large vein in your chest. The tube stays in place throughout the course of treatment. This can be a:

• central line
• PICC line
• portacath

If you don't have a central line

You might have treatment through a thin short tube (a cannula) that goes into a vein in your arm. You have a new cannula each time you have treatment.

Taking your tablets

Speak to your pharmacist if you have problems swallowing the tablets.

Whether you have a full or an empty stomach can affect how much of a drug gets into your bloodstream.

You should take the right dose, no more or less.

Talk to your healthcare team before you stop taking a cancer drug or if you miss a dose.

How often do you have R-DHAP?

You have R-DHAP as cycles of treatment. This means you have the drugs and then a rest to allow your body to recover.

Each cycle lasts 21 days (3 weeks). The number of cycles you have depends on your individual situation.

Rituximab can cause an allergic reaction. So before each dose you have paracetamol, a steroid and an antihistamine drug such as chlorphenamine (Piriton).

For the first cycle of rituximab, you have it as a drip into your bloodstream slowly over a few hours. This is to prevent an allergic reaction. Your nurse will increase how fast it goes in (rate) approximately every 30 minutes if you have no allergic reaction.

Your next rituximab drip will usually go in quicker, but this will depend on how you got on with the first cycle.

This is an example of one way of having R-DHAP treatment:

You then start a new treatment cycle.

Your nurse or doctor will give you steroid eye drops to use for about 5 days. This is to help prevent your eyes getting sore from the cytarabine.

You usually also have G-CSF. This is an injection under the skin (subcutaneous). It helps your body make white blood cells to lower your chance of getting an infection.

Tests

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.

Before treatment starts you have a blood test to check for viruses such as Hepatitis B infection or Cytomegalovirus (CMV) . This is because infection with these viruses can become active again if you’ve had them in the past. 

What are the side effects of R-DHAP?

Side effects can vary from person to person. They also depend on what other treatments you're having. 

When to contact your team

Your doctor, nurse or pharmacist will go through the possible side effects. They will monitor you 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. 

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 (more than 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).

Acute respiratory distress syndrome (ARDS)

Cytarabine can cause ARDS due to inflammation of the lungs from infection or injury. It causes a lack of oxygen to your organs such as the lungs, heart and brain. You might have symptoms that include fast and shallow breathing, tiredness, drowsiness, confusion, feeling like you will faint and shortness of breath.

An allergic reaction

Some people have an allergic reaction to rituximab. This reaction is most likely to happen during treatment and when you first have the treatment. Symptoms of an allergic reaction include high temperature (fever), chills, feeling or being sick and difficulty breathing. 

Your nurse will give you medicines beforehand to try to prevent a reaction. Tell your nurse straight away if you have any symptoms of an allergic reaction. They will slow down or stop your drip for a while.

Changes to how your liver is working

You might have liver changes that are usually mild and unlikely to cause symptoms. They usually go back to normal when treatment finishes. You have regular blood tests to check for any changes in the way your liver is working.

Feeling or being sick

Feeling or being sick is usually well controlled with anti sickness medicines. It might help to avoid fatty or fried foods, eat small meals and snacks and take regular sips of water. Relaxation techniques might also 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 treat it once it has started.

Skin changes

You might notice skin changes, such as dryness, itching and rashes. Less commonly you may develop a break in the skin (ulcer) and peeling skin.

R-DHAP can also cause a severe skin reaction, but this is rare. Symptoms usually start as tender red patches which leads to peeling or blistering of the skin. You might also feel feverish, and your eyes may be more sensitive to light. This is serious and could be life threatening

Tell your doctor or nurse if you have any of these symptoms so they can give you medicines to help.

Headaches

Tell your healthcare team if you keep getting headaches. They can give you painkillers to help.

Changes in levels of substances in your blood

You may have changes in levels of minerals and salts in your blood such as low levels of sodium. Your calcium levels can also drop, but this is less common. Rarely you might also get low levels of magnesium or high levels of uric acid that could possibly go onto cause gout.

You have regular blood tests during treatment to check this.

Tumour lysis syndrome

This is when you have changes to the levels of substances in your blood, due to the breakdown of cancer cells. It usually happens when you first start treatment, but you have regular blood tests to check for this.

You may need a drip with fluid and medicines such as allopurinol or rasburicase. This is to help prevent kidney damage and other side effects such as changes in your hearts rhythm and seizures (fits).

If you are at risk of developing tumour lysis syndrome you will have close monitoring when you first start treatment.   

Hair loss 

You could lose all your hair. This includes your eyelashes, eyebrows, underarms, legs and sometimes pubic hair. Your hair will usually grow back once treatment has finished but it is likely to be softer. It may grow back a different colour or be curlier than before. 

Diarrhoea

Contact your advice line if you have diarrhoea. For example, 2 or more extra loose bowel movements than usual each day. If you have a stoma, you might have more output than normal. Your doctor may give you anti diarrhoea medicine to take home with you after treatment.

Try to eat small meals and snacks regularly. It’s best to try to have a healthy balanced diet if you can. You don’t necessarily need to stop eating foods that contain fibre. But if your diet is normally very high in fibre, it might help to cut back on high fibre foods such as beans, nuts, seeds, dried fruit, bran and raw vegetables. 

Drink plenty to try and replace the fluid lost. Aim for 8 to 10 glasses per day.

Sore mouth and ulcers

Mouth sores and ulcers can be painful. It helps to keep your mouth and teeth clean, drink plenty of fluids and avoid acidic foods such as lemons. Chewing gum can help to keep your mouth moist. Tell your doctor or nurse if you have ulcers.

A build up fluid in different parts of the body

A build up of fluid (oedema) may cause swelling in your arms, hands, ankles, legs, face, lungs and other parts of the body. 

Fluid on the lungs can cause symptoms such as difficulty in breathing especially when you lay down, cough, and you may cough up blood or bloody froth.

Contact your doctor or nurse if you notice any swelling or have changes to your breathing.

Pain in different part of your body

This treatment can cause pain in different parts of your body such as the tummy (abdomen). Other sites of pain include your ear, neck, back, chest, or where the cancer is, but this is less common. Rarely you might have pain where the drip goes into the vein.

Let your treatment team know if you have this so that they can give you painkillers.

Cytarabine syndrome

Cytarabine syndrome sometimes happens about 6 to 12 hours after having this drug. 

It causes a combination of symptoms. These include a high temperature, aching muscles, bone pain, occasionally chest pain, a rash, sore eyes, and extreme weakness. Steroids can help to prevent or treat this syndrome.

Inflammation and ulcers of the opening at the end of the bowel (anus)

Talk to the team looking after you about this. They might be able to give you medicines or creams to help with this.

Feeling very sleepy

You might feel very tired or find you are falling asleep during the day. Do not drive or operate machinery. Let your doctor know straight away. 

Eye changes 

You might have eye problems including blurred vision, sore, red, itchy, dry eyes (conjunctivitis) or an infection. Tell your healthcare team if you have this. They can give you eye drops or other medication to help. 

Difficulty with movement and speech

You might have problems with your speech. You might be unsteady when you stand and find it difficult to walk. You might have no muscle control causing coordination problems.

Tiredness and weakness

You might feel very tired and as though you lack energy.

Various things can help you to reduce tiredness and cope with it, for example exercise. Some research has shown that taking gentle exercise can give you more energy. It is important to balance exercise with resting.

Occasional side effects

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

• blood clots that can be life threatening; signs are pain, redness and swelling where the clot is. Feeling breathless can be a sign of a blood clot in the lung. Contact your advice line or doctor straight away if you have any of these symptoms
• heart problems including changes to your heart rhythm. Contact your healthcare team straight away if you feel tightness in your chest, pain in your chest, feeling lightheaded, dizzy, pain in different parts of the body, sweating or anxious attack
• low blood pressure that can cause you to feel lightheaded or dizzy. Sometimes this can happen when you stand up from sitting or lying down (orthostatic hypotension)
• high blood pressure that might cause headaches, confusion, vision problems or chest pain
• numbness or tingling in fingers and toes that can make it difficult to do fiddly things such as doing up buttons
• changes to how well your kidneys are working- you will have regular blood tests to check for any changes 
• difficulty swallowing
• sore throat
• loss of appetite
• hearing changes such as ringing in the ears (tinnitus)
• sweating and night sweats
• weight loss
• high blood sugar levels – symptoms might include feeling very thirsty, passing urine very often, feeling tired, blurred vision, or weight loss
• difficulty falling or staying asleep
• dizziness
• feeling agitated or anxious. Rarely it can cause you to feel very low in mood (depressed) or nervous
• unusual feelings of the skin – such as numbness, tingling, pricking, burning, a creeping skin feeling, reduced sense of touch
• indigestion symptoms include heartburn, bloating, and burping
• high levels of a substance (enzyme ) called LDH in the blood - you will have blood tests to check this
• constipation
• feeling generally unwell
• runny nose
• flushing - sudden reddening and warmth of the neck, upper chest and face
• several body parts (organs) stopping working
• high levels of fat (cholesterol) in the blood
• lung problems such as breathlessness, chest pain, coughing, or tightening of the muscles that lines the airway (bronchospasm). Rarely you might have asthma or low levels of oxygen

Rare side effects

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

• a second cancer such as leukaemia
• swollen tummy (abdomen)
• problems with how your blood clots
• swollen lymph nodes
• taste changes
• a hole in your stomach or bowel (perforation)
• your kidneys may stop working – symptoms might include not passing enough wee, breathlessness, feeling tired and weak, confused, feeling sick, and you might have swelling on your legs, ankles and feet 
• seizures (fits)
• a blood disorder where your red blood cells get destroyed faster than they can be made (haemolytic anaemia)
• a condition where your bone marrow stops making your blood cells (aplastic anaemia)
• changes in the brain that are usually reversible, causing a sudden onset of symptoms including headaches, dizziness, confusion, fits (seizures) and changes to your vision
• a condition called cytokine release syndrome – when your immune system makes a large amount of cytokines . Symptoms include fever, chills, a headache, difficulty breathing, and dizziness

Other side effects

There isn't enough information to work out how often these side effects might happen. You might have one or more of them. They include:

• inflammation of the pancreas (pancreatitis) - symptoms include severe tummy pain, feeling or being sick, a high temperature or you may have loose poo
• weakening of the bones (osteoporosis) or broken bones (fractures)

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 medicines, herbal products, and some food and drinks. We are unable to list all the possible interactions that may happen. An example is grapefruit or grapefruit juice which can increase the side effects of certain drugs.

Tell your healthcare team about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies. Also let them know about any other medical conditions or allergies you may have.

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.    

Breastfeeding

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

If you are having tests or treatment for anything else, always mention your cancer treatment. For example, if you are visiting your dentist.

Immunisations

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 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. Sometimes people who have had the live shingles vaccine can get a shingles type rash. If this happens they should keep the area covered.

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 and possible side effects go to the electronic Medicines Compendium (eMC) website. You can find the patient information leaflet on this website.

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