How Long Do the Effects of Chemotherapy Last?

When it comes to options for cancer treatment, chemotherapy is often at the top of the list. Although the process is often life-saving, it does not come without its share of side effects. Many of the side effects of chemotherapy generally stop once treatment has completed; however, some side effects may take longer to heal, or may not heal at all. According to the National Cancer Institute, the severity of each side effect generally depends on what type of chemotherapy drugs are being used, and the schedule in which chemotherapy is administered.

Is This an Emergency?

If you are experiencing serious medical symptoms, seek emergency treatment immediately.

How It Works

Chemotherapy drugs are designed to target the cells of the body that have become cancerous. These cells are destroyed by the drugs interfering with the cancer cells' abilities to grow and divide. Unfortunately, chemotherapy drugs are unable to determine the difference between cancer cells and other cells that grow and divide at an accelerated rate in comparison to other cells in the body. This means that not only does chemotherapy kill cancer cells, it can also kill other important cells in the body such as those that make blood cells and those that are involved in the growth of hair.

Hair Loss

Because the body is constantly growing and replacing hair, these cells grow at an accelerated rate. As a result, they are targeted by chemotherapy drugs, causing the hair to fall out during treatment. Once the chemotherapy medications have been metabolized out of the body and treatment has ceased, in most cases, these cells begin to rebound. This allows those who have completed treatment to begin growing back their hair soon after treatment has finished.


Nausea and other stomach issues (such as vomiting and diarrhea) are also common side effects of chemotherapy. Nausea often results with chemotherapy because of the drugs' effects on the chemoreceptor trigger zone (CTZ) of the brain, more specifically the medulla. Once this center has been activated by chemotherapy, vomiting or nausea can occur. Once treatment has been completed, and the remaining chemotherapy medications have been metabolized by the body, the nausea and stomach issues should subside.

Blood Cell Counts

Another side effect of chemotherapy can be a lowered white and red blood cell count. Your blood cell counts can be lowered because of chemotherapy's effects on the bone marrow also known as bone marrow suppression. Bone marrow creates many of the blood cells in your system. Because chemotherapy is monitored carefully, in most cases enough bone marrow survives the chemotherapy treatment to rebound once treatment has been completed. Regular blood count tests will be done during your chemotherapy treatments to ensure that damage to the bone marrow is limited. Blood cell counts will begin to rise again once the chemotherapy drugs have been metabolized out of the body.

Permanent Effects

Not all side effects of chemotherapy are temporary. For example, permanent heart damage can be done with the use of anthracycline drugs for chemotherapy. The chemo drug bleomycin can cause permanent damage to the lungs. Other chemotherapy drugs raise the risks of permanent damage to the reproductive organs. Not everyone will suffer permanent side effects, but it is important to discuss with your doctor the side effects of the particular chemotherapy drugs they choose to use for your treatment.