Feeling very tired and weak

Chemotherapy can make you feel really tired, and this can get worse as your treatment goes on. It may also last for months after your treatment ends. This is called fatigue.

You might also feel weak and low on energy, which is known as lethargy. Both fatigue and lethargy are common side effects of chemotherapy.

Bruising and bleeding easily

You might notice that you:

Bruise more easily.
Get nosebleeds.
Have bleeding gums when brushing your teeth.

This happens because chemotherapy can lower your platelet count. Platelets help your blood clot, so when there aren’t enough, you may bruise or bleed more easily.

If your platelet count drops too low, you might see small red spots or bruises on your arms or legs. These are called petechiae. Let your doctor or nurse know right away if you notice this.

If needed, you may get a platelet transfusion through a drip (IV). It takes about 15 to 30 minutes. The new platelets start working immediately.

Higher risk of infection

Chemotherapy can lower your white blood cell count, making it harder for you to fight off infections. White blood cells help protect you from bacteria and viruses, so when their numbers drop, even a small infection can become serious quickly. In some cases, an infection can become life-threatening within hours.

Tell your hospital team right away if you have any signs of an infection, like:

A fever of 38°C or higher.
Feeling cold and shivery.
Headaches.
Aching muscles.
A cough or sore throat.
Pain when peeing.
A lower-than-normal temperature.

Call your hospital immediately—some infections can get serious very fast. You might need antibiotics through an injection or a drip because tablets may not be enough.

Since no one can predict if a fever will get worse, it’s important to treat all infections quickly. Your doctor will take it seriously, so don’t hesitate to reach out. It’s always better to be safe.

Hearing problems

Some chemotherapy drugs might cause problems like hearing loss or ringing in the ears. These problems usually get better after treatment is over. If this happens, your doctor may change your treatment or lower the dose. Be sure to tell your doctor or nurse if you notice any changes in your hearing.

Breathlessness and looking pale

Chemotherapy can lower the number of red blood cells in your body, a condition called anaemia. Red blood cells carry oxygen to your body’s cells, and when there aren’t enough, it can make you feel short of breath and look pale. If you notice this, let your doctor or nurse know.

You’ll have regular blood tests to check your red blood cell count. If it gets too low, you might need a blood transfusion. This will help you feel less breathless and look less pale.

Having low red blood cell levels can also make you feel tired or down, but you’ll likely start to feel better once your levels improve. Your blood count may change throughout treatment, so it’s normal to feel up and down physically and emotionally.

Eating and drinking

Chemotherapy drugs can sometimes make you feel sick or cause vomiting, but anti-sickness medications can usually help with this.

Some chemotherapy drugs can make the inside of your mouth sore or cause small mouth ulcers.
They can also change the way things taste for a while.
Certain chemotherapy drugs might irritate the lining of your bowel and cause diarrhoea, typically in the first few days after treatment.
This can usually be controlled with medication.
Some chemotherapy drugs, along with medicines for sickness, can also cause constipation (when you have difficulty passing stool).

Kidneys, liver, heart and lungs

Some chemotherapy drugs can cause changes in the way your kidneys, liver, heart or lungs work. The changes are usually temporary and go back to normal when your treatment ends. However, in some cases, the changes may last. Your doctor can tell you if your treatment might cause any of these changes.

Some chemotherapy drugs can also increase the risk of blood clots. If you feel short of breath or notice swelling in your leg, contact your hospital right away.

Chemotherapy can also make you lose your appetite. If you don't feel like eating for a few days after treatment, that's okay. You can catch up later, but it's important to drink plenty of fluids.

If you're worried about what to eat, or if you're having trouble with your stomach or losing weight, talk to your doctor, nurse, or dietitian.

Other common side effects of chemotherapy

Hair loss—will usually grow back in 3-6 months.
Upset stomach (nausea).
Mouth sores.
Changes in taste or hearing.
Changes in skin or nails.
Tingling in fingers or toes.
Anaemia.
Swelling in parts of your body like your legs, feet, or hands. This happens when your body holds onto extra water.
Vomiting.
Allergic reactions.
Muscle pain.
Diarrhoea.

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