Possible side effects

Possible side effects

Chemo drugs work by attacking cells that are dividing quickly, which is why they work
against cancer cells. But other cells in the body, like those in the bone marrow, the lining
of the mouth and intestines, and the hair follicles, also divide quickly. These cells are also
likely to be affected by chemo, which can lead to side effects. Some women have many
side effects; others may only have few.
The side effects of chemo depend on the type of drugs, the amount taken, and the length
of treatment. Some of the most common possible side effects include:
· Hair loss
· Mouth sores
· Loss of appetite or increased appetite
· Nausea and vomiting
· Low blood cell counts
Chemo can affect the blood forming cells of the bone marrow, which can lead to:
· Increased chance of infections (from low white blood cell counts)
· Easy bruising or bleeding (from low blood platelet counts)
· Fatigue (from low red blood cell counts and other reasons)
These side effects are usually short-term and go away after treatment is finished. It's
important to tell your health care team if you have any side effects, as there are often
ways to lessen them. For example, drugs can be given to help prevent or reduce nausea
and vomiting.
Other side effects are also possible. Some of these are more common with certain chemo
drugs. Your cancer care team will tell you about the possible side effects of the specific
drugs you are getting.

Menstrual changes: For younger women, changes in menstrual periods are a common
side effect of chemo. Premature menopause (not having any more menstrual periods) and
infertility (not being able to become pregnant) may occur and may be permanent. Some
chemo drugs are more likely to do this than others. The older a woman is when she
receives chemotherapy, the more likely it is that she will become infertile or go through
menopause as a result. When this happens, there is an increased risk of bone loss and
osteoporosis. There are medicines that can treat or help prevent problems with bone loss.
Even if your periods have stopped on chemo, you may still be able to get pregnant.
Getting pregnant while receiving chemo could lead to birth defects and interfere with
treatment. This is why it’s important that women who are pre-menopausal before
treatment and are sexually active discuss using birth control with their doctor. Patients
who have finished treatment (like chemo) can safely go on to have children, but it's not
safe to get pregnant while on treatment.
If you are pregnant when you get breast cancer, you still can be treated. Certain chemo
drugs can be safely given during the last 2 trimesters of pregnancy. This is discussed in
detail in the section, “Treatment of breast cancer during pregnancy.”
Neuropathy: Several drugs used to treat breast cancer, including the taxanes (docetaxel
and paclitaxel), platinum agents (carboplatin, cisplatin), vinorelbine, erubulin, and
ixabepilone, can damage nerves outside of the brain and spinal cord. This can sometimes
lead to symptoms (mainly in the hands and feet) like numbness, pain, burning or tingling
sensations, sensitivity to cold or heat, or weakness. In most cases this goes away once
treatment is stopped, but it might last a long time in some women.
Heart damage: Doxorubicin, epirubicin, and some other drugs may cause permanent
heart damage (called cardiomyopathy). The risk of this occurring depends on how much

of the drug is given, and is highest if the drug is used for a long time or in high doses.
Doctors watch closely for this side effect. Most doctors order a test like a MUGA or an
echocardiogram (to check the patient’s heart function) before starting one of these drugs.
They also carefully control the doses, watch for symptoms of heart problems, and may
repeat the heart test to monitor heart function. If the heart function begins to decline,
treatment with these drugs will be stopped. Still, in some patients, heart damage takes a
long time to develop. They may not show signs of poor heart function until months or
years after treatment stops. Heart damage from these drugs happens more often if the
targeted therapy drug trastuzumab is used as well, so doctors are more cautious when
these drugs are used together.
Hand-foot syndrome: Certain chemo drugs, such as capecitabine and liposomal
doxorubicin, can irritate the palms of the hands and the soles of the feet. This is called
hand-foot syndrome. Early symptoms include numbness, tingling, and redness. If it gets
worse, the hands and feet become swollen and uncomfortable or even painful. The skin
may blister, leading to peeling of the skin or even open sores. There is no specific
treatment, but these symptoms gradually get better when the drug is stopped or the dose
is decreased. The best way to prevent severe hand-foot syndrome is to tell your doctor
when early symptoms come up, so that the drug dose can be changed. This syndrome can
also occur when the drug 5-FU is given as an IV infusion over several days (which is not
commonly done to treat breast cancer).
Chemo brain: Another possible side effect of chemo is "chemo brain." Many women
who are treated for breast cancer report a slight decrease in mental functioning. There
may be some problems with concentration and memory, which may last a long time.
Although many women have linked this to chemo, it also has been seen in women who
did not get chemo as a part of their treatment. Still, most women do function well after
treatment. In studies that have found chemo brain to be a side effect of treatment, the
symptoms most often go away in a few years. For more information, see our document,
Chemo brain.
Increased risk of leukemia: Very rarely, certain chemo drugs can permanently damage
the bone marrow, leading to a disease called myelodysplastic syndrome or even acute
myeloid leukemia, a life-threatening cancer of white blood cells. When this happens it is
usually within 10 years after treatment. In most women, the benefits of chemo in
preventing breast cancer from coming back or in extending life are likely to far exceed
the risk of this serious but rare complication.
Feeling unwell or tired: Many women do not feel as healthy after receiving chemo as
they did before. There is often a residual feeling of body pain or achiness and a mild loss
of physical functioning. These may be very subtle changes that are only revealed by
closely questioning women who have undergone chemo.
Fatigue is another common (but often overlooked) problem for women who have
received chemo. This may last up to several years. It can often be helped, so it is
important to let your doctor or nurse know about it. For more information on what you

can do about fatigue, see our document, Fatigue in People with Cancer. Exercise, naps,
and conserving energy may be recommended. If there are sleep problems, these can be
treated. Sometimes there is depression, which may be helped by counseling and/or
medicines.