Cancer treatment affects everyone differently. While some people experience only mild side effects, others may have symptoms that affect their daily activities.
Many side effects can be managed with the right treatment, practical strategies and support. Always let your healthcare team know if you experience new or worsening symptoms, as early intervention can often prevent them from becoming more serious.
Why do side effects happen?
Cancer treatments work by destroying or slowing the growth of cancer cells. In the process, some healthy cells may also be affected, leading to temporary side effects.
The type and severity of side effects vary depending on your treatment and your individual health. Your healthcare team will explain the side effects you may experience and how to manage them.
When should I contact my healthcare team?
Some side effects require prompt medical attention. Contact your healthcare team immediately if you:
- Develop a fever or signs of infection
- Have severe or persistent vomiting or diarrhoea
- Are unable to eat or drink for an extended period
- Experience sudden shortness of breath or chest pain
- Have severe or worsening pain
- Notice unusual bleeding or bruising
- Experience any symptom that concerns you or feels different from what you were told to expect
If you are unsure whether a symptom is serious, it is always safer to seek medical advice.
Common side effects and how to manage them
Fatigue
Feeling tired is one of the most common side effects of cancer treatment. You may find it helpful to:
- Prioritise important activities.
- Take regular rest breaks throughout the day.
- Maintain a balanced diet.
- Stay physically active with gentle exercise if recommended by your healthcare team.
- Accept help from family and friends when you need it.
Speak to your healthcare team if fatigue becomes severe or affects your daily life.
Nausea and vomiting
Some cancer treatments may cause nausea or vomiting. You can help manage these symptoms by:
- Taking anti-nausea medications exactly as prescribed.
- Eating small, frequent meals.
- Drinking fluids regularly to stay hydrated.
- Avoiding foods or smells that trigger nausea.
Seek medical attention promptly if you cannot keep fluids down or become dehydrated.
Pain
Pain can often be managed successfully with medication and other supportive treatments.
To help manage pain:
- Take pain medication as prescribed.
- Do not wait until pain becomes severe before taking medication, unless advised otherwise.
- Tell your healthcare team if your pain changes or worsens.
Never ignore persistent or worsening pain.
Appetite loss
It is common to lose your appetite during treatment.
You may find it helpful to:
- Eat small meals more often throughout the day.
- Choose foods that are high in protein and calories.
- Drink fluids between meals rather than during meals if you feel full quickly.
- Eat in a comfortable, relaxed environment.
If appetite loss continues, ask to speak with a dietitian for personalised advice.
Hair loss
Not all cancer treatments cause hair loss, but it can be an emotional experience for many people.
Some people choose to:
- Cut their hair shorter before treatment.
- Wear hats, scarves or wigs.
- Talk openly with family, friends or a counsellor about how they are feeling.
Remember that hair usually begins to grow back after treatment has ended, although it may look or feel different initially.
Dry mouth
Treatment may reduce saliva production, making your mouth feel dry.
To help relieve dry mouth:
- Sip water regularly.
- Maintain good oral hygiene.
- Rinse your mouth with a salt and baking soda solution if recommended by your healthcare team.
- Avoid alcohol and excessive caffeine.
Speak to your doctor if your symptoms persist, as medications may help.
Constipation
Constipation may occur because of certain treatments, medications or reduced physical activity.
To help relieve constipation:
- Drink plenty of fluids.
- Stay physically active if possible.
- Eat fibre-rich foods if appropriate.
- Speak to your healthcare team before taking laxatives or stool softeners.
Fertility and sexual wellbeing
Some cancer treatments can affect fertility, sexual function or intimacy.
If you are planning to have children in the future, discuss fertility preservation with your healthcare team before treatment begins whenever possible.
It is also important to ask about any precautions regarding sexual activity during treatment. Open communication with your partner can help you navigate these changes together.
Looking after your wellbeing
Managing side effects is about more than treating physical symptoms. Many people also find it helpful to:
- Stay connected with family and friends.
- Join a support group.
- Take part in gentle physical activity where appropriate.
- Speak to a counsellor if they are feeling overwhelmed.
- Celebrate small milestones throughout treatment.
Remember that everyone responds differently to treatment. Avoid comparing your experience with others, and focus on what feels manageable for you.
Support beyond treatment
Managing side effects can affect many aspects of daily life, from your physical well-being to your confidence and emotional health.
Singapore Cancer Society offers programmes and services to support patients throughout treatment, including rehabilitation, psychosocial support, financial assistance and the Look Good Feel Better programme.
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We're here to support you
Managing side effects can be challenging, but you don’t have to do it alone.
Singapore Cancer Society offers programmes and services to support you throughout treatment.
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