Side effects of chemotherapy

Alopecia (hair loss)

Hair loss, particularly on the scalp, occurs from two weeks after the first treatment. Hair may fall out gradually or quickly, in clumps. Hair on the rest of the body, e.g. eyebrows, eyelashes, facial hair, hair in the underarm or pubic regions, may also be variably affected. Hair will begin to grow back about four to six weeks after the last treatment; this will be fine and may be curly initially.

The Ministry of Health provides subsidies for wigs and headwear. Patients should take care to apply sunscreen to their scalp, if they are outside and not wearing a head covering. Bimatoprost 0.03% eye drops may help to prevent chemotherapy-induced eyelash loss. Patients should discuss this treatment with their oncologist.

Gastrointestinal toxicity (nausea, vomiting, diarrhoea)

Chemotherapy-induced nausea and/or vomiting can be well controlled with anti-nausea medication. This side effect can be more pronounced among patients who have a history of severe pregnancy-induced nausea or travel sickness. Patients should take care to maintain adequate fluid intake and report severe or persistent diarrhoea or vomiting to their oncology team.

Nail damage

Chemotherapy treatment, particularly docetaxel and paclitaxel, can cause the finger or toenails to become brittle and pigmented, develop ridges or fall off.

Neutropenia

Chemotherapy can cause neutropenia, making patients more susceptible to infection. Low white blood cell count typically happens 10-14 days after each cycle, however docetaxel may cause this drop to happen 5-9 days after each cycle. If patients develop neutropenia, their next chemotherapy cycle may be delayed or the dose reduced; in some regimens, they will be given injections of white blood cell growth factors to maintain an adequate cell count. Patients will be given information about being alert for infection and who to contact if they have signs of infection.

Treatment can also cause anaemia and low platelet counts. Blood counts will be monitored with regular blood tests during treatment.

Mucositis

Mucotisis is the inflammation and/or ulceration of the mouth lining, resulting in a sore mouth or ulcers. It can be managed with alcohol-fee mouthwashes, adequate fluid intake, regular lip balm use and gentle teeth cleaning with a soft brush. Patients should notify their oncology team if mucositis is severe.

Peripheral neuropathy

Chemotherapy drugs can cause nerve pain, tingling or numbness, particularly in the hands and feet. These usually resolves after treatment but may persist long-term. Patients should report any peripheral neuropathy to their oncology team.

Weight gain

Some patients may experience weight gain as a result of drugs causing metabolic changes, a sedentary lifestyle during treatment or eating more to prevent nausea, and chemotherapy-induced early menopause.

Cognitive changes

Problems with concentration and short-term memory can be a side effect of chemotherapy, and these side effects are often referred to as ‘chemo brain’. The severity and duration of symptoms will differ between patients; some will find this side effect mild where it resolves after treatment, while others will find that it noticeably affects their daily life for a longer period of time. For these patients, ‘chemo brain’ may restrict their ability to return to normal activities in their pre-treatment capacity. There is no standard treatment for cognitive changes, but management can involve the following strategies:

• Getting adequate rest and sleep.
• Reducing stress through yoga, meditation, relaxation techniques, etc.
• Using organisational tools (e.g. planner, to-do-list) to keep track of appointments, family and work schedules.
• Regular exercise.
• Following a healthy diet and restricting alcohol intake.

Fatigue

Fatigue during chemotherapy may be a direct effect of the drugs used or may be due to other causes, e.g. disrupted sleep patterns. Energy levels typically recover once treatment ends, but for some patients, full recovery may take up to 12 months or more. Regular exercise can help with fatigue. If patients are unable to exercise due to fatigue, they should discuss this with their GP.

Heart conditions

Certain chemotherapy drugs (e.g. doxorubicin, epirubicin) and targeted therapies (e.g. trastuzumab) increase the risk of heart problems. Patients will have their heart health assessed before treatment starts and monitored during treatment. Patients should follow a healthy lifestyle to reduce the risk of developing heart problems.

Menopause

Premenopausal women will undergo ovarian suppression while on chemotherapy. This protects ovarian function while reducing the risk of recurrence in patients with hormone receptor-positive breast cancer. Many patients will recover their ovarian function after treatment ends, and can expect menstruation to resume within 12 months. Even if menstruation does not resume, some patients will still be fertile. However, in some patients, treatment can induce early menopause and the resulting loss of fertility. The closer a patient is to the onset of natural menopause, the less likely it is that ovarian function will recover. This risk is heightened in patients receiving chemotherapy over the age of 40.

Chemotherapy-induced menopause is more sudden than natural menopause, and symptoms (e.g. hot flushes, vaginal dryness) may be more severe initially. Menopause also reduces bone density; patients should speak to their oncologist about maintaining bone health and managing menopausal symptoms.