Head and neck radiotherapy side effects
The main side effects from radiotherapy to the head and neck include:
- mouth problems
- problems with your teeth
- weight loss
- difficulty swallowing
- changes to your voice
- swelling in your neck and face (lymphoedema)
You may also experience more general side effects of radiotherapy such as hair loss, sore skin and tiredness.
Like all side effects of radiotherapy, you might not feel these straight away. Side effects tend to come on gradually as you go through your treatment. And for a few weeks afterwards. Everyone reacts differently to radiotherapy, so how you feel varies from person to person.
Problems with your mouth and teeth
During radiotherapy you may have problems with your mouth and teeth. These can include:
The cells lining your mouth are sensitive to radiation. Radiotherapy is likely to make your mouth sore and you might have ulcers after a week or so. This is called oral mucositis.
The soreness usually only lasts while you are having treatment and for a few weeks afterwards. Your radiotherapy team can give you painkillers to help. Following a mouthwash routine from the start of radiotherapy will also help.
You might need to have a feeding tube into your stomach if your mouth is sore and stopping you from eating or drinking properly.
Smoking and alcohol can make the soreness worse. You can try to cut down on smoking. Talk to your radiotherapy team about nicotine replacement treatments to help with this.
This video shows people affected by cancer, talking about having a sore mouth as a side effect from radiotherapy for head and neck cancer. The video is around 2 minutes long.
Voice over: When having radiotherapy to your head and neck, you can experience many different side effects. One of these might be a sore mouth.
Louise: Mouth soreness and throat soreness with head and neck radiotherapy is very common unfortunately. If the soreness is on the outside on your skin, they might recommend particular creams that you can use to help with that.
If the pain is internal, you may be referred to the doctor and the doctor will suggest some medication to help control the pain.
Charlie: Probably I think it was from week 2 to week 3 when the radiotherapy side effects started really impacting me. At that point, really, I was unable to eat. The ability to take food down your food tract with that level of inflammation and ulcers was just too difficult.
Louise: Mouth soreness can continue for up to 3 months. The team will support you during that time, whether that be with some medication or some skin care advice. They'll also check your mouth quite regularly to make sure you don't have an infection which might be slowing down the recovery time.
Charlie: They always checked the condition of my mouth and made sure that it was in good health, recovering, and if there was any issues they just supported and advised me on the best way to deal with it.
Voice over: For information on other head and neck radiotherapy side effects, visit the Cancer Research UK website.
Your treatment might affect the salivary glands so that they produce less or no saliva. It can be uncomfortable to chew or swallow. Let your radiographer or doctor know if you're having problems.
After the treatment ends it can take some time for saliva production to get back to normal. If the radiotherapy treatment area includes the salivary glands, you might have a permanently dry mouth afterwards. Your doctor will talk to you about this before you start treatment.
Some of the following tips might help:
- Ask your doctor to prescribe medicines that stimulate saliva.
- Sip drinks often to keep your mouth moist.
- Moisten your food with sauces, gravy, cream, custard or ice cream.
- Chewing sugarless gum can make your salivary glands produce more saliva.
- Clean your tongue with a liquid made from a teaspoonful of bicarbonate of soda in a litre of warm water.
- Use lip balm to keep your lips moisturised.
- Use moistened cotton wool or a soft toothbrush to clean your tongue.
- Ask your doctor to prescribe artificial saliva sprays or gels.
This video shows people affected by cancer, talking about having a dry mouth as a side effect from radiotherapy for head and neck cancer. The video is around 1 minute long.
Voice over: When having radiotherapy to your head and neck, you can experience many different side effects. One of these might be a dry mouth.
Charlie: My saliva glands were very close to some of the areas affected by cancer, so they did warn me that there was a high likelihood that my saliva glands would have some problems.
Louise: Radiotherapy can cause damage to the salivary glands. There are lots of things you can do to help with that. Small sips of water can ensure that your mouth stays moist. Little spritzer sprays or nebulisers, steam treatments can also help.
Charlie: Even now my saliva glands still don't work as well as they did beforehand. You'll find me sipping on water on a regular basis to offset the impact of the saliva gland limitation.
Voice over: For information on other head and neck radiotherapy side effects, visit the Cancer Research UK website.
Radiotherapy can make it easier for infections of the mouth to develop, such as thrush. The radiotherapy team will check your mouth regularly during your treatment.
Let your doctor or nurse know if you have any white patches on the inside of your mouth or on your tongue. They can prescribe medicines to help.
Radiotherapy can affect your taste buds. You might notice changes in the way your food tastes. Some people say their food has a metallic taste. Others say that all foods taste the same.
The radiotherapy team can arrange for you to talk to a hospital dietitian for advice about overcoming taste changes.
There are ways to help make food tastier. But you might need to wait to try these until your mouth has recovered from the treatment and is not sore any more.
This video shows people affected by cancer, talking about having changes to their taste as a side effect from radiotherapy for head and neck cancer. The video is around 1 and a half minutes long.
Voice over: When having radiotherapy to your head and neck, you can experience many different side effects. One of these might be changes to how things taste.
Louise: You may find that your taste alters. If this is the case, you might find that food and drinks that you previously loved do taste very different. Sometimes people report they taste a bit metallic. If this is the case, please consult your dietitian and they will be able to support you with that.
Tasha: It's like a battery taste. I don't know how I know that, but that's how I'd best describe it. It’s very unpleasant. So anything you're eating, you can't taste that food. It's just metallic taste.
At the end of my treatment, it still carried on, but it was slowly dying down and then when it went, I was very happy because I ate as much as I wanted.
Voice over: For information on other head and neck radiotherapy side effects visit the Cancer Research UK website.
You visit a dentist before you start radiotherapy to the head and neck. They look for any teeth that might be decaying or already decayed and will remove them. This is because radiotherapy makes it more likely that your teeth will decay so it's best to take them out first to avoid problems. Your mouth will also not heal as quickly after radiotherapy.
You'll also need to go for check ups at the dentist more often. Fluoride treatment might help to protect your teeth. You can have this as a mouthwash to use twice a day.
Remember to tell your dentist that you have had radiotherapy to your mouth before you have any dental work. Your dentist might need to change the way they treat you. They may also need to talk to your radiotherapy doctor before giving you any treatment.
This video shows people affected by cancer, talking about changes to their teeth as a side effect from radiotherapy for head and neck cancer. The video is around 1 and a half minutes long.
Voice over: When having radiotherapy to your head and neck, you can experience many different side effects. One of these might affect how you care for your teeth.
Louise: Radiotherapy can cause some bone weakening, so as a result of that, we would recommend you are referred to a dentist before you start a course of radiotherapy.
They will look at all of your teeth and any teeth that already appear weak and damaged may be removed before you start treatment.
Tasha: The dentist and even the doctors and consultants said that after you've had radiotherapy and if it's been near the mouth area or teeth that it can make dental treatments more painful, and I did find that.
Charlie: Post treatment you have to really, really look after your teeth, so I go to the dentist every 3 months. Any problems with your teeth have to be nipped in the bud.
Voice over: For information on other head and neck radiotherapy side effects, visit the Cancer Research UK website.
Difficulty swallowing
Radiotherapy for cancer in the head or neck area can cause swelling and soreness in the throat. Your throat might be very sore, and you may find it difficult to swallow solid food (dysphagia). You might need to have strong painkillers if your throat is too sore to swallow food. Or have a feeding tube fitted.
Whether you have problems swallowing depends on which part of the head or neck you are having treatment to. It also depends on the dose of treatment. Difficulty swallowing may be worse and can last longer if you have chemotherapy at the same time as radiotherapy.
You may see a Speech and Language Therapist (SLT) before you start treatment if this is likely to affect your swallowing. An SLT can assess your swallowing during and after treatment. They can teach exercises to support you with swallowing difficulties. And they work with a dietitian if you are finding it difficult to eat.
Talk to your healthcare team if you have any problems swallowing.
Weight loss
Radiotherapy to your head and neck area can make you lose weight. This can be because you have mouth problems such as a sore or dry mouth, which can make swallowing difficult. You may also have a poor appetite.
These effects might be temporary and gradually go back to normal after treatment ends. But for some people, the effects may be permanent. There are things you can do to help keep your weight up.
It's important to maintain your weight during radiotherapy treatment. Your radiotherapy is planned very precisely using your body measurements. This means if you lose or gain weight during radiotherapy it can change the amount of radiation that the cancer or nearby healthy cells receive. Losing too much weight might also make you feel weaker.
During your radiotherapy treatment:
- you might see a dietitian once a week who can help to advise you on foods that are easier to eat
- your doctor or dietitian may give you nutritional supplements, such as high calorie drinks to help keep your weight up
- your doctor might prescribe strong painkillers if your throat is very sore and you have pain when swallowing
- try not to drink alcohol (especially spirits) or smoke because this can make your mouth and throat very sore
If eating becomes very difficult you might have a feeding tube put into your stomach through your skin. Or a liquid feed through a drip. Some hospitals might arrange for you to have a feeding tube before you start radiotherapy. This is to stop you from losing too much weight. This varies from hospital to hospital.
This video shows people affected by cancer, talking about weight loss as a side effect from radiotherapy for head and neck cancer. The video is around 2 minutes long.
Voice over: When having radiotherapy to your head and neck, you can experience many different side effects. One of these might be weight loss.
Louise: Unfortunately, weight loss with head and neck radiotherapy is very common. Obviously we don't want you to lose too much weight, so we would work very closely with the dietitian to support you.
Charlie: The clinical team in advance warned me I would lose weight. They told me to prepare for it. They told me to eat lots of calories in advance and I thought they were kidding, but the reality is, the weight did drop very, very quickly.
Louise: Initially, if you start to notice any problems eating, we would recommend you start to move to a slightly softer diet. Foods that are soft, easy to swallow, but highly nutritious.
Charlie: Soups and gravies and maybe move on to scrambled eggs and rice puddings.
Louise: If you then find that that starts to become problematic, we do have some special little drinks that you can use as a meal replacement.
Tasha: I had a smoothie drink that was given to me by the doctors. It's like a smoothie with calories in and it's a small bottle so you're just topping up what you’re missing not eating and drinking fully.
Charlie: My swallow mechanism just stopped working, so everything I had to take was being taken through the stomach tube.
Louise: Occasionally the radiotherapy can have a real impact on how easily you can swallow and if it starts to become very problematic, they may suggest they use feeding tubes to help ensure you are getting the right nutrients.
Voice over: For information on other head and neck radiotherapy side effects, visit the Cancer Research UK website.
Changes to your voice
Your voice might get hoarse if you have radiotherapy to your voice box to treat cancer of the larynx. It could disappear completely for a while during and after the treatment. Your voice should come back within a few weeks but may never sound quite the same as it was.
Radiotherapy for other types of head and neck cancer might make your voice change a little during and for a few weeks after the treatment. Your voice should go back to normal once your treatment ends.
You might find it useful to carry a small notebook and pen so that you can always write notes to people if you need to.
Laptop computers or electronic notebooks are other ways you can communicate. Various types of small portable machines are available. Your speech and language therapist can advise you on which may suit you best.
This video shows people affected by cancer, talking about having changes to their voice as a side effect from radiotherapy for head and neck cancer. The video is around 4 minutes long.
Voice over: When having radiotherapy to your head and neck, you can experience many different side effects. One of these might be changes to your voice.
Charlie: They found cancer in my voice box so that was part of the treatment area. As the weeks progressed in treatment, I started losing it.
Louise: If you're having radiotherapy to your larynx, your voice box, you may well find that you end up with an altered voice. This can happen during treatment and we can't always guarantee your voice will be the same as it was after treatment.
Charlie: I lost it in total probably for maybe 2 weeks, so my wife had a peaceful couple of weeks for that period of time, and it just came back. But it was quite fragile. So I learned to take it easy, and even now, 18-20 months after treatment, I can feel it if I talk too much.
Louise: We would recommend you rest your voice as much as possible and if needed, carry a pen and paper around with you, so you can continue to communicate.
Voice over: For information on other head and neck radiotherapy side effects visit, the Cancer Research UK website.
Swelling in the neck and face (lymphoedema)
After radiotherapy for head and neck cancer, you are at risk of getting swelling called lymphoedema in your neck or face. Lymphoedema is pronounced lim-fo-dee-ma.
Lymph fluid is in all body tissues. It comes from the tiny blood vessels into the body tissues. Usually, it drains back into the bloodstream through channels called lymph vessels. These are part of the lymphatic system.
A build up of lymph fluid in an area of the body can happen if lymph drainage channels or 
are blocked, removed or damaged. This causes swelling.
Radiotherapy can cause changes in the lymphatic system in the head and neck area. It's a long-term (chronic) condition. It can’t be cured, but it can usually be well controlled.
Sometimes the cancer itself can affect your lymphatic system and cause lymphoedema.
Symptoms can include:
- swelling of your tongue and other parts of your mouth
- swelling or a feeling of fullness or pressure
- difficulty swallowing
- changes to your voice
Symptoms may develop soon after treatment. Or it can take many months or a few years to appear after radiotherapy.
What to do if you have symptoms
Contact your doctor or specialist nurse if you know you’re at risk of lymphoedema and you have any of the symptoms above. Early treatment can help to control swelling and stop it getting worse. Your doctor or nurse can refer you to a lymphoedema specialist.
The Lymphoedema Support Network can tell you how to get lymphoedema care within the NHS.
The British Lymphology Society has a directory of lymphoedema services.
Lymphoedema is easier to control if treated early. It is important that you are referred to a lymphoedema specialist if you have signs of swelling. This is usually a nurse or physiotherapist.
An underactive thyroid (hypothyroidism)
If your thyroid gland is in the radiotherapy treatment area, you may develop an underactive thyroid. This is called hypothyroidism. It can develop a few months or years after treatment.
Common symptoms of hypothyroidism include:
- tiredness
- weight gain
- feeling cold
- constipation
- joint or muscle pain
- poor memory
If left untreated it can cause heart problems.
You have regular blood tests to check your thyroid hormone levels after treatment.
If you develop hypothyroidism, you take medicine to replace the thyroid hormone. This is usually a tablet you take every day. This normally improves your symptoms but it can take several months.
Worries about treatment side effects
You may feel anxious about radiotherapy side effects and this is normal. It can help to talk through any worries you have with your doctor, nurse or radiographer.
You can talk to the Cancer Research UK nurses for general information and support on freephone 0808 800 4040, from 9am to 5pm, Monday to Friday.
