Early Side Effects


Chemoradiation therapy results in some very painful side-effects to the mouth and throat.  One of the most common is mucositis, a collection of symptoms related to the destruction of the cells lining your mouth and throat, a very sensitive part of your body! Here we detail some of the most common symptoms, and provide real patient experiences as to what to expect, and tips on how to cope with it.

Common symptoms include:
• Swollen mouth and gums
• Sores, including persistent mouth ulcers, that may bleed
• Soreness and pain in the throat and mouth
• Difficulty in eating food and drinking water
• Difficulty in swallowing
• Difficulty in talking
• Dryness, pain and sometimes burning sensation in the mouth when eating food
• White patches on the tongue and elsewhere in the mouth
• Thick mucus production, and thick, gloopy saliva

Anson, HNC patient 2020 reflects:
At the start of my third week of radiation therapy, I could feel my gums becoming tingly. Overnight, 15+ ulcers appeared along the right side of the mouth (I lost count as ulcers merged into each other), across my tongue, and even on my lips. Some of the ulcers were huge, sticking out over 5mm, meaning that I wasn't able to close my jaw, as they would get crushed by my back teeth. The ulcers at the front of my mouth and on my bottom lip meant that I couldn’t move my lips, which meant that my mouth was permanently open, tense but immovable. I also couldn’t speak. And these are alongside the increasing rawness along my throat, tonsils and roof of mouth, from the radiation burns that are starting to accumulate, and increasing thickness of my saliva, which is pretty gross. 


Harvey, HNC patient 2023 reflects:
Despite following the dentist’s advice on keeping my mouth clean, two weeks into the radiotherapy my saliva glands stopped working and I began to get ulcers at the back of my throat. By week 3 I had one huge ulcer on the roof of my mouth and this stayed with me until 4 weeks post treatment. I found that gargling with saline solution helped but if we overdid the salt, I would be doubled over in pain. My throat was super sore but with the aid of painkillers and consultant prescribed meds to aid swallowing, I managed to keep eating soft foods and water until week 6 of my treatment and then reverted to my RIG for Fortisips and liquid food. I used a humidifier on my bedside table to help lubricate my throat at night. The use of a nebuliser helped manage the mucus build up from week 5 until 2 weeks post treatment.

It is of course important to have good dental and mouth hygiene, but normal tooth-brushing will become painful, as will use of many mouth-washes. We recommend that you brush your teeth with the softest tooth-brush that you can find, and use a very mild mouthwash (with no alcohol content), but only if possible.

Perhaps one of the biggest problems associated with mucositis will be your inability to eat food, and maybe even to drink water,which can affect your ability to recover. You may also have lost your sense of taste (while some taste sensations can become even stronger!). Together, these affect the amount that you will want, and be able to eat and drink. 

You should aim for*at least* 2-3 thousand calories and 2-3 litres of water every day. If you have a feeding tube fitted (e.g. RIG, PEG or nasogastric), definitely use it, as it will make all the difference in keeping your calorie intake high. You should be prescribed calorific nutrition drinks (e.g. Fortsip), which often do not taste very nice. But this is not a problem if taken through your feeding tube! If you are unsure, ask your assigned dietician; they are there to really help you to keep eating food and drinking enough fluids. 

Thick saliva and mucus production

At some point during your treatment, or shortly after treatment ends, you may notice that you start to produce a lot more saliva and mucus in your throat and mouth. These will turn thick and gloopy, and production may be constant.

Debbie, HNC patient September 2023 writes:
Mucus started to be produced by the end of week two (having completed one 10hr overnight chemo session (cisplatin) and 10 radiotherapy sessions ). At first it was white & frothy, and reasonably thin so easily wiped away /spat out. But this quickly developed into a thicker consistency by session 15 (end of week 3). By session 25 (week 5) it began to get more troublesome and more frequent, and I had to pull the mucous out with my fingers. Night times and mornings were always worse, and I had a few scary moments, choking on what looked like thick glue! 

By the end of my treatment plan, I asked my clinical nurse specialist for a suction machine, and this really helped. It was noisy but it took the sticky thick mucus away in seconds (and also saved me from using 5 boxes of tissues a day!!). I had also tried humidifier / mouthwashes / soda water and Carbusistine but sadly nothing helped. 

Post treatment, my mucus became very thick and colourful: clear/white/yellow/green or brown. Production got worse until week 8 post treatment, and then as if by magic it became thinner and less frequent. By week 12 I  now use suction occasionally and only need a small pack of tissues a day!

Anson, HNC patient 2020 reflects:
The week after my daily radiation therapy had finished, glutty green phlegm started to build up in my throat. I was producing so much, but because it was so thick, the only way I could get rid of it was to wretch. Around the same time, I also started to produce a constant supply of  thick, mucus-like saliva that had to be wiped away constantly. For about 6 days I had to lie on towels every night as I literally could not stop drooling this stuff. 

As mentioned above, this is not a pleasant side-effect, and it can be distressing for yourself and others to hear you coughing and retching. You will need lots of cloths and tissues to collect phlegm and wipe away mucus. You may also find an oral suction device, with suction tube, really helpful - ask your speech and language therapist for details. 

Dry Mouth

You may not know this, but your mouth contains many different types of salivary gland and they are very sensitive to radiation treatment. Unfortunately, radiation therapy for head and neck cancer can lead to irreversible damage to some or most of your salivary glands cells. This in turn leads to marked changes in the quantity and quality of your saliva - you will likely produce less saliva, and what you do produce may be thicker - technically this is called xerostomia, or dry mouth. Over time, your dry mouth will improve in most people to a greater or lesser degree. However, your experience of having a dry mouth can be permanent (see Late side effects below), and have a major impact on your quality of life, altering what you can eat and drink. When head and neck cancer patients meet up, a common topic of conversation is what you can and cannot eat - invariably spicy food is eaten less, and alcohol drunk less, but not for all people! 

Having a dry mouth is serious. It can lead to opportunistic infections (mostly fungal such as thrush), radiation-induced tooth decay, salivary stones and cysts, and burning mouth syndrome. Having a dry mouth will lead to difficulty in eating, swallowing, and speaking, increase the risk of cavities and dental disease, and complicates denture maintenance. Patients with a dry mouth or xerostomia should maintain adequate oral hygiene to minimize the risk of oral lesions. Xerostomia can lead to periodontal disease and extensive tooth decay - see late side-effects below.

Hazel HNC patient July 2018 writes:
My dry mouth is still with me now five years post treatment. I do manage it and it is nothing like it was at the start, but if you imagine your worst ever hangovers  that was my mouth for a good 2.5 years post treatment. For me, none of the saliva sprays that you get prescribed work. My long suffering husband was fed up with me saying my mouth is dry on repeat. Imagine the Sahara desert - that was my mouth! 

I found that a small water bottle with a spray was better than constantly drinking water because constant drinking washes away what little bit of saliva that you have. So the water spray bottle is a better alternative. Saying that, I still did drink 2 to 3 L of water, tea and coffee which are themselves dehydrating so be careful as  they make  the dry mouth symptoms worse!!  Herbal teas do help when your  mouth can tolerate them. At night time I use Xylimelts which we have to buy as they are not a prescription item but are found easily online. 

Now I find that my dry mouth is liveable during the day, but at night I  still use half an Xylimelt, and that lets me get a full night's sleep. Although I  don’t wake  with a dry mouth anymore, a glass of water is always at the bedside. 

Dani, HNC cancer patient,  December 2018 remembers:
Five years ago I finished six weeks of radiotherapy for base of tongue cancer. Radiotherapy severely impacted my salivary glands but I have made a reasonable recovery albeit with a few ups and downs over the years. Now I find I can eat almost anything and only some things need a little sip of water to help things along. Some reminders remain. 

At the beginning I tried lots of gels and saliva substitutes, but one of them worked for me because they were either too sticky, too smelly, or too awful tasting. Soon after, a friend mentioned that she had tried acupuncture. So I trawled the internet till I found a practitioner who said she might be able to help me with a practice called auricular acupuncture. Needles in my ears…OK. Needles in my fingers…Ouch! but lo and behold after the first session I had saliva in my mouth and after sessions for a year I was a new woman.

Dry mouth at night! How can this be? For years I was fine but now sometimes I wake with my mouth as dry as dust…I had runs of this for days until I stumbled on a solution. Sleep tape.
I cut it down as the idea of wearing something right over my mouth is a bit alarming…And I can, if I need,  have a drink through a straw and to my delight, I now wake in the morning to a perfectly moist mouth full of saliva. Honest! The things we do! My husband thinks it’s hilarious. [Dani has supplied a photo here if we want to use it]

Nowadays I carry sugar free gum. Some days I have to chew madly through the day but most of the time the gum remains in my jeans pocket. I have discovered Salivix pastilles which are really good for a quick boost if I can’t be seen chewing and I still pop in a Xylimelt at night.
All in all I’m still very aware that my saliva is not what it was but it will do.

A reduction in saliva means I have to be OTT with oral hygiene, especially frequent brushing with high fluoride toothpaste, never eating sweet food except as part of a meal, and regular visits to my hygienist. I get a fluoride varnish every three months it’s definitely something I would recommend

What we’ve found from listening to people is that what might work for someone, will not necessarily work for others. But many measures can help in coping with xerostomia, or a persistent dry mouth, such as having some form of fluid nearby all the time. These fluids can be drunk or sipped or even sprayed into your mouth. Depending on the severity of the dry mouth, some people prefer diet soft drinks over water. Gargling with weak salt solutions can help to loosen thick oral secretions, alleviate mouth ulcer pain as well as helping to combat build up of any dangerous bacteria.

Many people swear by sugar-free sweets or gum to suck or chew, with products such as Xylmelts developed specifically for dry mouth conditions. At night, keeping water by your bedside is helpful, and some people find that Xylmelts also help. Some people use a bedside humidifier at night, and raising the head of the bed can be helpful too. 

Avoiding smoking is recommended, and minimising alcohol intake as well. Many people find drinking alcohol, especially spirits or strong wines, too sore anyway. 

Acupuncture has been found helpful in stimulating saliva glands. Using a high-fluoride toothpaste, such as Duraphat, is also recommended, and if living in the UK you should be able to get this as a free prescription from your dentist or GP. 

Having a dry mouth will also likely change your dietary habits, from dry, crusty, tough food to food that is moist and easier to swallow e.g. food with a sauce. Many people (but not all) find that they are more sensitised to spices, but tolerance may over the years be built up again. 

Eating in public may be problematic, as it can take twice as long to eat a meal as others, and bought foods often do not declare they contain chilli! Many foods which sound OK can therefore end up being unpalatable. Gradually you will find what you can and cannot eat. We recommend telling friends and family in advance what is possible for you - they will come to remember, recognise and understand your new dietary requirements. 


Both radiation therapy and chemotherapy can cause short-term and long-term fatigue. The feeling of fatigue is not the same as tiredness,  and it may be difficult to explain what you feel, physically, emotionally and psychologically. 

Harvey, HNC patient 2023 reflects:
My Radiotherapy sessions mainly happened in the mornings and by 3pm in the afternoon I was feeling very tired. I got into a routine of sticking a film on, lying on the settee and having a “nana nap” for an hour or so. I would feel much better afterwards. I believe that maintaining regular exercise is very important during treatment to combat fatigue and I was even able to play golf a couple of times a week up to week 5 of treatment. Walking the dog was my main exercise though. I found that having a Fortisip helped boost my energy levels whilst exercising, particularly if I started to feel dizzy. Despite all the calorie intake, I lost 1 and half stones in weight and 4 weeks post treatment I was having prolonged dizzy spells. My GP then halved my hypertension meds to reset and balance my blood pressure which was too low!

Fatigue can come in waves - you can’t fight it and it is best that you listen to your body and take things easy, have an extended rest, or even have a nap if tired. Over time, the fatigue should get less common, but can still hit you like a wave, even a year into the future. Again, listen to your body and take things easy for a bit. Ask your employer about reducing your hours or changing what you need to do at work, just until the fatigue improves.  

Digestive Issues

Chemotherapy can cause you to feel sick, have diarrhoea, be constipated, lose your appetite, and develop mouth problems like ulcers and thrush. Which of these will develop will depend on the type of drug you are given, its dose, and for how long you take it. Some but not all chemotherapy drugs can cause nausea and vomiting. And even with those that do, people will be affected to different degrees. Your oncologist should provide you with anti sickness tablets (antiemetics) to take before the sickness begins to help prevent the worst side-effects. If the antiemetic drug you are given doesn’t work, ask your oncologist for a different type - there are many.

Some chemotherapy drugs can cause diarrhoea, and it is important to drink lots of fluids if this happens. If your diarrhoea is severe or continuous despite drugs to halt it, then you should seek advice from your hospital. Conversely, constipation may be caused by some chemotherapy drugs, but also the drugs used to treat sickness, and drugs used to relieve pain. You will have been given a laxative to take at home to help with constipation.

Chemotherapy can also lead to lower numbers of white blood cells and generally lower immunity. This means that you may develop thrush, especially in the mouth, alongside ulcers. These will be almost impossible to distinguish from ulcers and thrush you may get from the radiation therapy (see above). If you develop thrush, tell your oncologist and they will prescribe you a drug to get rid of it. 

Finally, chemotherapy will likely cause you to lose your appetite. It is essential that you maintain a high calorie intake to remain well and recover from your treatments. Also, you want to prevent weight-loss around your head and neck, as this could cause your mask to become ill-fitting during radiation treatment - see below.

Harvey, HNC patient 2023 reflects:
I had 3 chemo doses of Cisplatin and 35 radiotherapy treatments. The first chemo dose didn’t cause me too many problems with nausea but the second dose caused a multitude of issues. Not only did I feel nauseous, I also developed tingly fingers, tinnitus, hiccups and for a couple of nights I slept with hiccups which was most disconcerting for my wife! I went back to my oncologist who added more meds to my pill count to stop the hiccups. Apparently this side effect is quite rare and proves that everyone reacts differently, you just had to raise it with your support team. When it came to discussing the third dose of chemo with my oncologist, I was very nervous about what was to come. We decided to stick to Cisplatin and although I was physically sick more times than before, I had the right drugs to keep all the other side effects at bay. Looking back, I’m glad I stuck to the plan and was given the gold standard for my type of HNC.

Weight Loss

It is perhaps unsurprising that the majority of  patients who undergo treatment for head and neck cancer will suffer weight loss during treatment and the immediate recovery phase. As seen above, mucositis makes it too painful to eat, while xerostomia makes it too difficult to eat. Chemotherapy can cause nausea and act as an appetite suppressant, while general fatigue from chemoradiation therapy will result in a lack of appetite as well. 

For people undergoing chemoradiation therapy, losing weight becomes a major problem, because there is a risk that the mask will become ill-fitting, which will make the targeting of the radiation beams less precise as your face and head quickly change shape. You should have been prescribed high-calorie nutritional supplements that quickly become an essential part of your diet, as they pack in the calories and are relatively easy to drink, or to take through your feeding tube. 

Anson, HNC patient 2020 reflects:
I got scared because of what I’d been told about the consequences of not eating and drinking enough. If I couldn’t eat and drink enough, then I would lose weight, energy, and would dehydrate. From a radiation therapy point of view, this could lead to my mask not fitting and therefore compromising the targeting of the radiation beams. My mouth was also more prone to infection and sepsis, which again, could have had serious implications for future treatment. I was initially resistant about using my feeding tube, but once I realised how useful it was it became my best friend, and I took the majority of my fluids and nutrition through it, and managed to stabilise my weight loss. 

If it is suggested you have a feeding tube fitted, having one will make all the difference down the line when your mouth and throat are too sore to eat and drink normally. Try to eat a varied diet, although the time will come when you will only be able to tolerate certain foods. It is important to take the high calorie nutrition supplements prescribed to you during treatment and recovery.  

Chemotherapy induced peripheral neuropathy (CIPN)

CIPN occurs when specific chemotherapy drugs can cause neural damage, leading to a range of effects including numbness, sudden pain, and / or pins-and-needles in the hands and feet, ringing in your ears (e.g. tinnitus), suddenly feeling hot or cold, or loss of balance, or difficulty in going to the toilet, or difficulty in manipulation your fingers to do what was once a simple task like tying a shoe-lace.  

Effects can occur soon after you start the chemotherapy, and can last a lifetime. Because the range of problems that can arise are so varied, recommendations for alleviating the symptoms are varied too.

Anson, HNC patient 2020 reflects:
I was prone to tinnitus before I was diagnosed with cancer in 2020. However after I was treated with cisplatin the tinnitus got worse, and I had to find new ways of dealing with it. I don’t know if the two things are related, but since having chemotherapy, I became profoundly deaf in my left ear, such that I now need to wear a hearing aid. It was at this time that my tinnitus got worse. There are many suggestions on the Web for how to deal with tinnitus, and how to make sure it doesn’t disrupt your sleep. For me personally, I find I am able to ignore it during the day time, but at night I wear bone-conduction earphones to listen to the radio as I fall asleep and I find this distracts me enough from the tinnitus. During the day, I also wear a hearing aid, especially when I go out, or friends come round.

Harvey, HNC patient 2023 reflects:
My CIPN affects my fingers and toes, particularly my left hand and my right foot. It started with pins and needles after my second dose of chemo and has developed into annoying sensitivity bordering on pain. I wear gloves and thick socks more now in cold weather to relieve the symptoms and I definitely prefer warm and hot weather. I exercise my fingers by pressing each one to my thumb and applying pressure which seems to help. I’m told it can take months for the CIPN to reduce but I’m resigned to it being my lasting present from chemo.

If you develop tinnitus whilst having chemotherapy, please make your oncology team aware. It may be possible to change the drug, e.g. cisplatin, to a gentler one e.g. carboplatin.  


Lymphodoema in head and neck cancer patients can occur when your lymph nodes are either removed by surgery or damaged due to chemoradiation treatment. When the lymph nodes are damaged, lymph fluid (that normally occurs in fatty tissues just under your skin) does not get removed, and so builds up, causing swelling of the head and neck. As well as swelling, the skin can start to feel very tight, and may change in texture, and become red, and even feel hot. The greater the build up of fluid, the greater the chance of infection as well.

Debbie, September 2023
I first noticed swelling under my chin and around jowls 6 weeks post-radiotherapy treatment. It was actually difficult to notice at first, as I still had swelling on my neck from treatment.  By week 7 I asked my MacMillan champions (Hazel and Dani; amazing heroes!) advice, after remembering reading something on their blogs. Following their advice I began doing   massage and exercises, also contacting my clinical nurse specialist by email (sending photos) requesting support from Lymphedema service asap. She referred me immediately, and within a week I was given an appointment. At the first appointment, the  lymphoedema nurse gave me a neck compression garment and a 30min MLD (manual lymphatic drainage) massage which softened the lymphedema. The nurse also advised me to buy a jade roller and showed me how to use this.

I’m now 12 weeks post treatment, have a more comfortable garment and weekly MLD. Managing lymphoedema is time consuming. Also, it is uncomfortable and the visible deformity has impacted on my self esteem. I really think that more awareness/ information and specialised support is needed for Head and Neck cancer patients.

If you experience lymphoedema, contact your assigned cancer nurse as soon as possible. Lymphatic drainage massage can be a very effective way to ease lymphedema with expert help, and you should be able to get a referral. 

Early Side-Effects

Side-effects experienced during treatment and in the months just after treatment, sometimes called the recovery period

Late Side-Effects

Side-effects that may occur from one year to many years in the future after treatment. Descriptions, patient reflections and recommendations