Chemotherapy is a common treatment for cancer. Depending on the type of cancer, different combinations of medications may be used as part of a chemo treatment plan.

In general, chemotherapy medications work by attacking cells, or by preventing cells from growing and dividing. Cancer cells tend to grow and divide rapidly and uncontrollably. Many chemotherapy drugs are designed to target this type of rapid cell growth.

However, the body is made up of many types of cells, including healthy cells that naturally grow at a fast pace. Chemo treatments can’t differentiate between cancer cells and healthy cells. That’s why chemotherapy harms or kills healthy cells, as well as cancer cells.

Many common side effects of chemotherapy are caused by the treatment’s impact on healthy cells.

Different doses and types of chemo can cause different side effects, which may include:

  • anemia
  • fatigue
  • diarrhea
  • constipation
  • infection
  • peripheral neuropathy (numbness, tingling, pain)
  • easy bruising and bleeding
  • appetite changes
  • mouth, tongue, and throat problems (sores, problems swallowing)
  • skin and nail changes (dry skin, color change)
  • fertility problems
  • mood changes
  • “chemo brain” (problems with concentration, focus)
  • a weakened immune system
  • hair loss
  • urine, bladder, and kidney problems
  • nausea

Although chemotherapy has the potential to cause side effects, not everyone gets them, and they can vary in severity. Knowing what’s happening in your body may help you to understand side effects during treatment.

Since chemo drugs can’t tell the difference between cancer cells and healthy cells, the treatment can affect many types of healthy cells, especially rapidly dividing ones.

The healthy cells most likely to be damaged by chemo include:

  • blood-forming cells in bone marrow
  • hair follicle cells
  • cells that make up the mucus membranes of the mouth, throat, and digestive system

Some chemo drugs can also damage cells in the heart, kidney, bladder, lungs, and nervous system.

The damage that chemotherapy causes to these cells can lead to certain side effects.

Your doctor may recommend medications to help protect your body’s healthy cells while you are undergoing chemo treatment. Additionally, there are treatments that can help relieve side effects.

Here are eight common side effects of chemotherapy and the treatment methods to help manage them.

Red blood cells provide your body with oxygen from the lungs. When chemotherapy harms red blood cells and lowers red blood cell counts, chemo-induced anemia can occur.

The main symptoms of anemia are tiredness and weakness. However, anemia can also cause:

  • irregular heartbeat
  • shortness of breath
  • dizziness
  • cold hands or feet
  • headaches

If you’re undergoing chemotherapy, your cancer care team will monitor your blood cell count closely. Anemia can be treated with an iron-rich diet, iron supplements, or in some cases, blood transfusions.

White blood cells are a vital part of the body’s immune system. When chemotherapy significantly lowers white blood cell counts, a condition called neutropenia occurs.

Neutropenia makes it harder for the immune system to fight off viruses, bacteria, and other pathogens. This means a person’s risk of infection is increased.

Symptoms of neutropenia include:

  • fever
  • chills
  • mouth sores
  • cough
  • difficulty breathing
  • abdominal pain
  • rectal pain

It’s important for people receiving chemo to take steps to avoid getting sick. Washing hands regularly, avoiding crowded places, and staying away from people who may be sick may decrease a person’s risk of infection. Careful food preparation and cooking can also reduce the risk of food poisoning.

Neutropenia can be treated with proteins called myeloid growth factors, which stimulate the production of white blood cells. Antibiotics may also be used. Additionally, cancer treatment may be delayed temporarily to allow the body time to make more white blood cells.

Chemotherapy may affect platelets, a component of the blood that helps it clot and stop bleeding. A low platelet count is called thrombocytopenia. When this occurs, your blood isn’t able to clot properly, which can lead to excessive bleeding.

Additionally, cancer patients, particularly those who receive chemotherapy, are at an elevated risk of developing a type of blood clot called deep vein thrombosis (DVT.) This is when a blood clot forms in a deep vein.

Your cancer care team will keep track of your blood cell counts to assess your risk for thrombocytopenia and blood clots.

Some patients with low platelet counts may need to be treated with a platelet transfusion, a type of blood transfusion. People at risk of developing blood clots or DVT may be recommended to take blood thinners.

Hair follicle cells are some of the fastest-growing cells in the body. Because many chemotherapy treatments target rapidly dividing cells, hair loss is a common side effect of treatment.

However, not all types of chemo cause hair loss. When chemotherapy does cause hair loss, it usually grows back after treatment stops.

Wearing a scalp cooling cap before, during, and after chemotherapy infusions may help prevent or reduce hair loss.

Nausea and vomiting are common side effects of chemotherapy.

While the exact causes of chemo-induced vomiting and nausea aren’t fully understood, they’re likely due to certain areas of the brain being triggered during treatment. When these parts of the brain are triggered, they activate a reflex pathway through areas of the esophagus, causing the sensation of nausea and vomiting.

There are different types of nausea and vomiting that may occur in people undergoing chemotherapy:

  • Acute nausea and vomiting can happen within minutes to hours after treatment is given.
  • Delayed nausea and vomiting starts more than 24 hours after treatment and can last for days.
  • Anticipatory nausea and vomiting can happen before treatment begins and is a learned response that develops as the result of previous chemo treatments that led to nausea and vomiting.
  • Breakthrough nausea and vomiting happen despite treatment being given to prevent it.
  • Refractory vomiting is vomiting that does not respond to treatment. It may happen after several chemo treatments.

There are many combinations of drugs and treatments that may help prevent or control vomiting and nausea in people undergoing chemotherapy.

Mucositis is another side effect of chemotherapy, which can cause sores, bleeding, and pain in the mouth and throat. It occurs when chemo causes a low white blood cell count.

Mucositis can make everyday tasks like eating and drinking difficult, or even impossible.

Increasing how often you brush your teeth, having regular dental exams, keeping your mouth moisturized, and not smoking may help prevent or shorten the duration of mucositis. Prescription medication is also an option.

Mucositis typically gets better within a few weeks of finishing chemotherapy treatment.

Chemotherapy can cause short-term or long-term mental changes in the brain, commonly referred to as “chemo brain,” or post-chemotherapy cognitive impairment. It’s described as a decrease in mental sharpness following chemo.

Brain fog can make it hard to remember certain words or memories, concentrate on tasks, and learn new skills. People experiencing brain fog may have trouble multi-tasking or remembering names or common words.

Treatment for chemo-induced brain fog includes cognitive rehabilitation activities to help improve brain function, as well as exercise and meditation.

Chemotherapy can cause changes to a person’s nails and can create discoloration, blemishes, and dryness. Nails may look bruised and turn black, brown, blue, or green, and can become abnormally thin or brittle. In some cases, the nail can completely lift off the nail bed or fall off.

Nail changes can increase a person’s risk of infection, so it’s important to take steps to keep nails trimmed and clean.

Tips to decrease the risk of nail infection include wearing gloves when gardening or cleaning, painting nails to increase strength, and avoiding biting and picking at nails.

Although chemotherapy may cause a variety of side effects, many are short-term, and certain people feel no side effects at all.

If you are preparing to undergo chemotherapy, you should talk to your doctor about which side effects to expect, how long they should last, and when you should report them.

You should also ask your doctor if the chemo drugs you’re taking have any long-term side effects.

Most side effects are treatable and will go away or diminish after treatment has stopped. Medications, dietary changes, and complementary therapies are effective treatment options for a wide range of side effects.

The goal of chemotherapy depends on the type of cancer, its location, and a person’s unique circumstances. Based on the specific goal, there are three main categories of chemo treatment:

  • Curative: The therapy attempts to destroy all cancer cells, so that a person is cancer-free.
  • Adjuvant or neoadjuvant: The therapy targets cancer cells remaining in the body after surgery or attempts to shrink cancerous growths prior to surgery.
  • Palliative: If the cancer cells can’t be eliminated, treatment may focus on relieving symptoms or slowing cancer growth.

Chemotherapy is often just one part of a larger treatment plan. It may be given with other treatments like radiation, surgery, or other medications.

Chemotherapy is a treatment that attempts to destroy or harm cancer cells. At the same time, it often impacts healthy cells, causing certain side effects. Most of these side effects are short-term and treatable.

Your cancer care team can help you understand your specific chemo plan, how it’s expected to work, and what side effects may occur.