Chemo is a lifesaving treatment, but it also causes side effects in all of the body’s systems.

After receiving a cancer diagnosis, your first reaction may be to ask your doctor about chemotherapy, also known as chemo.

After all, chemotherapy is one of the most common forms of cancer treatment. But chemotherapy does a lot more than get rid of cancer.

While chemotherapy drugs are powerful enough to kill rapidly growing cancer cells, they can also harm healthy cells. This may cause a variety of side effects. The severity of these side effects depends on:

  • your overall health
  • the stage of your cancer
  • the type and amount of chemotherapy you receive

Many side effects clear up shortly after treatment ends, but some may continue for months, years, or may never go away.

It’s important to discuss any side effects you’re experiencing with your doctor. Depending on how your body reacts, your doctor may need to adjust the type or dose of chemotherapy.

Chemotherapy drugs can affect any body system, but may especially impact the following:

  • digestive tract
  • hair follicles
  • bone marrow
  • mouth
  • reproductive system

It’s worth understanding how these cancer drugs can affect your major body systems:

An illustrated graph of how chemo affects the body. Share on Pinterest

Routine blood count monitoring is a crucial part of chemotherapy. The drugs can cause a loss of healthy red blood cells, resulting in anemia.

Symptoms of anemia may include:

  • fatigue
  • lightheadedness
  • pale skin
  • shortness of breath
  • chest pain
  • rapid heart rate

Treating chemotherapy-induced anemia may involve blood transfusions or medications. A doctor may also recommend iron supplements.

Chemo can also cause neutropenia, a condition where you have a low white blood cell count. White blood cells play an essential role in the immune system and help fight infections. It’s important to take precautions to avoid exposure to viruses and bacteria if you’re receiving chemo, including keeping up with your vaccinations.

A low platelet count, called thrombocytopenia, can also occur with chemotherapy. Cells called platelets help blood clot. Low numbers of them mean you’re likely to bruise and bleed easily. Symptoms may include:

Some chemo drugs may also damage the heart, potentially leading to cardiomyopathy, or heart muscle disease. It can also disturb your heart rhythm, a condition called arrhythmia. These conditions can affect your heart’s ability to pump blood effectively.

These problems are less likely to occur if your heart is strong and healthy when you start chemotherapy.

The central nervous system controls emotions, thought patterns, and coordination. Chemotherapy drugs may cause problems with memory or make it difficult to concentrate or think clearly. This is sometimes called “chemo brain.”

Chemo brain is usually temporary, but for some people, these changes may be long-term or permanent. Severe cases may add to existing anxiety and stress.

Chemo drugs can also cause a variety of other issues with your nervous system based on which nerves are damaged. Symptoms can include:

Unsteadiness and difficulty balancing also increase your risk of falling. Working with an occupational or physical therapist may help you improve your motor skills and coordination.

Consuming frequent or larger doses of chemotherapy drugs increases the likelihood of pain and discomfort in your mouth or throat. Certain types of chemo also affect your mucosa (inner mucus lining of some organs) more than others. You may experience:

You may also develop mouth sores on your tongue or gums. These can make you more susceptible to infection and make it harder to eat and get good nutrition.

If you have trouble eating or the treatment causes food to taste unusual or unpleasant, it may lead to unintentional weight loss.

Chemotherapy drugs can also harm cells along the gastrointestinal tract. This can cause:

You can lessen these symptoms by drinking plenty of water during the day.

Nausea is another common chemotherapy symptom that may result in vomiting, leading to dehydration and decreased appetite. Many cancer clinics give anti-nausea medications as part of their chemotherapy drugs. If a medication isn’t working, the doctor can try a different type of anti-nausea medication to help manage the symptom.

Even if you don’t feel hungry, it’s important to continue eating healthy foods. It may help to try foods that are soft and easy to swallow.

Eating small, frequent, nutrient-dense foods instead of large meals is a good way to increase caloric intake. It may also offset weight loss and fatigue. Smoothies and shakes that contain protein, fruits, and vegetables are a great way to have these foods in a palatable way.

Hair loss is perhaps the most well-known side effect of chemo treatments. Many chemotherapy drugs affect hair follicles and can cause hair loss, known as alopecia, within a few days or weeks of the first treatment.

Hair loss can happen anywhere on your body but is most likely to occur on your scalp. New hair growth usually begins several weeks after the final treatment.

Minor skin irritation is possible, too, including:

  • dryness
  • itchiness
  • peeling
  • rash

Your doctor can recommend topical ointments to soothe irritated skin.

You may also develop sensitivity to the sun and burn more easily. Wearing sunscreen, long sleeves, and a hat can help shield your skin when outdoors.

Additionally, your fingernails and toenails may turn yellow and become brittle. In severe cases, they may separate from the nail bed. Moisturizing your cuticles and cutting your nails short may help.

Chemotherapy drugs alter hormones in both males and females. In females, chemotherapy can affect the ovaries, potentially causing:

In males, some chemo drugs can harm sperm or lower sperm count. Like females, males can have temporary or permanent infertility from chemo.

Doctors advise against getting pregnant during chemotherapy treatment. Chemotherapy drugs can damage sperm and can also harm the fetus if given during pregnancy, possibly leading to developmental issues for a fetus.

If you are already pregnant when you receive a cancer diagnosis, you still have options. You and your doctor will discuss the next best steps. Treatment may involve surgery rather than chemo, or different timing of treatment.

While symptoms like fatigue and anxiety may interfere with sex drive in both men and women, many people on chemotherapy are still able to have active sex lives.

The kidneys work to excrete the chemotherapy drugs as they move through your body. In the process, some kidney and bladder cells can become irritated or damaged.

Symptoms of kidney damage include:

Some chemo medications may cause urine to turn red or orange for a few days. You may also experience bladder irritation, which causes a burning sensation when urinating and increased urinary frequency.

Your doctor will likely recommend that you drink plenty of fluids to help keep your system functioning properly.

It’s common to lose bone mass with age, but some chemo drugs can increase this loss. In females, chemo may damage the ovaries, so they stop making estrogen. Lower estrogen levels lead to bone loss.

According to a 2020 review, women treated for breast cancer are at increased risk of osteoporosis and bone fracture. The most common areas of the body to experience breaks are:

  • spine
  • hips
  • wrists

You can help keep your bones strong by:

Many cancer centers will give people at risk of chemo-related osteoporosis a bone medication alongside their treatment to help prevent bone loss. Alternative treatments can also help prevent or ease osteoporosis.

Living with cancer and undergoing chemotherapy can affect your mental health. It’s typical to feel a range of emotions, such as:

  • fear
  • stress
  • denial
  • anger
  • hope
  • depression
  • anxiety

Talking with friends and family may help you process your emotions. Your healthcare team may also be able to suggest a local cancer support group where you can speak with others undergoing cancer treatment.

If feelings of depression persist, look for professional counseling or talk with your doctors. While emotional side effects are common, there are ways to reduce them and increase your quality of life.

Chemotherapy may cause additional side effects in rare cases. These include:

Some of these uncommon side effects may be minor, while others can be life threatening. Contact your doctor if you experience any unusual symptoms.

Some side effects of chemotherapy can put you at risk of serious complications. For example, neutropenia (a low number of white blood cells) may be life threatening if you get an infection.

Chemotherapy may also cause long-term effects, such as:

  • heart damage
  • lung damage
  • kidney problems
  • nerve damage
  • infertility

Some chemo drugs may also increase your risk of developing a second cancer. There’s a greater chance of this happening if you receive higher doses of chemo over a longer period.

After completing treatment, your medical team will likely give you a survivorship care plan, which will contain information to continue screening for potential long-term complications.

Side effects are different for each person, so it’s difficult to predict how chemotherapy will affect you. Still, you can ask your doctor:

  • Which side effects are common with your chemo medication?
  • When might you experience side effects and for how long?
  • Which symptoms or side effects may need further treatment?
  • When should you call your doctor if you have certain symptoms?

Once you’re familiar with the side effects that you may experience, you can prepare for them by planning to rest, taking time off, or asking for help with energy-consuming commitments such as child care after chemotherapy.