Chemotherapy uses medicines that damage rapidly dividing cells. Cancer cells divide faster than most normal cells, which is why they are hit hardest — but some healthy fast-dividing tissues, such as hair follicles, the lining of the mouth and bone marrow, are affected too. That is the origin of most side effects.
Why it is given in cycles
Each cycle is a treatment day followed by a recovery gap, usually two or three weeks. The gap lets normal tissues — especially bone marrow — recover while the cancer does not have time to regroup. Blood counts and organ function are checked before every cycle, and treatment is delayed if the counts are unsafe.
The four intentions behind chemotherapy
- Curative — the main treatment aiming to eliminate the cancer, common in blood cancers
- Neoadjuvant — before surgery, to shrink the tumour
- Adjuvant — after surgery, to reduce the risk of recurrence
- Palliative — to control advanced disease and relieve symptoms
Side effects and what is done about them
- Nausea and vomiting — largely preventable with modern anti-emetics given routinely
- Low white cells and infection risk — managed with growth factor injections and clear fever instructions
- Fatigue — real and cumulative; paced activity helps more than complete rest
- Hair loss — drug-dependent and temporary
- Mouth ulcers — reduced with salt-water rinses and good oral care
- Nerve tingling — reported early, as the dose can be adjusted
When to call your doctor urgently
- Fever of 100.4°F (38°C) or above
- Bleeding, or unexplained bruising
- Persistent vomiting or an inability to keep fluids down
- Breathlessness, chest pain or reduced urine output
Frequently asked questions
Does chemotherapy hurt?
The infusion itself is not painful. If you feel pain, burning or swelling at the drip site, tell the nursing staff immediately.
Can I eat normally during chemotherapy?
Yes, with sensible precautions — freshly cooked food, adequate protein and good hydration. Raw and street food is best avoided when counts are low.
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Medical disclaimer: This page is general health information, not medical advice. Cancer treatment decisions depend on your reports, stage and overall health. Please consult a qualified oncologist before acting on anything you read here.