Nervous System Side Effects

Approved by the Cancer.Net Editorial Board, 05/2017

Nervous system side effects are common from cancer and cancer treatments. Relieving such side effects is an important part of cancer care. This is called palliative care or supportive care. Talk with your health care team about any symptoms you experience, including any new symptoms or a change in symptoms.

About the nervous system

The two main parts discussed below make up the nervous system.

  • Central nervous system (CNS). The brain and spinal cord are part of the CNS.

  • Peripheral nervous system (PNS). The nerves outside of the CNS that carry information back and forth between the body and the brain are part of the PNS. The PNS helps control the following:

    • Movement

    • Sensing, such as touching, hearing, seeing, tasting, and smelling

    • The functioning of the internal organs, such as the stomach, lungs, and heart

Symptoms of nervous system side effects

Nervous system symptoms may lead to a cancer diagnosis, appear soon after treatment, or may appear several years after treatment. The symptoms you experience depends on the part of the nervous system that is affected.

Symptoms of CNS changes

  • Cognitive or thought-process changes including decreased memory, problem solving, and calculation

  • Problems with balance, dizziness, nausea, and vertigo, which is feeling like the room is spinning

  • Problems with coordination

  • Seizures

Symptoms of peripheral nerve changes (peripheral neuropathy)

  • General weakness that causes an overall lack of strength and coordination, including problems with walking or holding objects

  • Numbness, tingling, or burning in the hands or feet

  • Constipation

  • Incontinence, which is not being able to control the flow of urine

  • Erectile dysfunction, which is being unable to get or maintain an erection

Learn more about peripheral neuropathy.

Symptoms of cranial nerve changes

The cranial nerve is also part of the PNS but can cause some distinct side effects, such as:

  • Hearing loss and/or a ringing in the ears called tinnitus

  • Vision loss and/or side effects such as blurred or double vision

  • Changes in taste and smell

  • Slurred speech or difficulty expressing oneself or understanding speech

  • Difficulty swallowing

Causes of nervous system side effects

Many factors cause nervous system side effects, including cancer, cancer treatments, other medications, or other health conditions. Learning the cause of nervous system changes is important to find the best ways to manage the symptoms. Below is a list of the possible causes of nervous system problems:

Cancer. Cancers that start in the brain or spinal cord or have spread to the brain or spinal cord may affect the CNS. A tumor in another part of the body may press on a peripheral nerve causing problems.

Chemotherapy. Specific drugs are more likely to cause nervous system side effects. These include:

  • Vinca alkaloids, including vincristine (Vincasar), vinorelbine (Navelbine), and vinblastine (Velban)

  • Platinum-based drugs, such as cisplatin (Platinol) or oxaliplatin (Eloxatin)

  • Taxane drugs, such as docetaxel (Taxotere) and paclitaxel (Taxol)

  • Etoposide (Vepesid)

  • Cytarabine (Cytosar-U), in high doses

  • Ifosfamide (Ifex), in high doses

  • Methotrexate (multiple brand names), in high doses

Changes to the CNS from chemotherapy are more likely to happen when chemotherapy is injected into the spine.

Surgery. Nerves may be damaged during surgery to remove a tumor or do a biopsy. A biopsy is the removal of a small amount of tissue for examination under a microscope.

Radiation therapy. Radiation therapy to the brain and/or spine can cause CNS problems. Radiation therapy to the head and neck or whole body may cause problems with peripheral nerves.

Other medications. Some other medications may affect the nervous system. These include:

  • Some drugs to prevent vomiting

  • Opioid pain relievers

  • Anticonvulsants, which are drugs to treat seizures

Other cancer-related side effects. Other conditions or symptoms related to cancer or cancer treatments can affect the nervous system.

  • Anemia, which is a low number of red blood cells

  • Fatigue

  • Stress

  • Depression

Other non-cancerous conditions. Infections causing swelling or inflammation of the brain, spinal cord, or inner ear can affect the CNS or peripheral nerves. In addition, other conditions that can affect the nerves includes diabetes, thyroid problems, human immunodeficiency virus (HIV), stroke, Alzheimer’s disease, and multiple sclerosis.

Nutrition and hydration. Dehydration and vitamin deficiencies can also affect how well the nerves work.

Managing nervous system side effects

Nervous system side effects can make it difficult for people to complete their usual daily activities. Some symptoms caused by cancer treatment will go away after treatment ends, but some may be ongoing. Although nerve damage and nervous system side effects may not be preventable, most are manageable if found early.

Early treatment can also prevent the symptoms from worsening. It is important to tell your doctor immediately if you have any of the symptoms listed above. Once diagnosed, management of nervous system side effects depends on the type of problem and the cause.

The following list provides several ways to manage nervous system problems. Talk with your health care team about which options are recommended for you.

Medicines. Some nervous system symptoms can be managed or treatment with medicines. These include:

  • Medicines for nausea and vertigo, such as meclizine (Antivert), prochlorperazine (Compazine), scopolamine patch (Transderm-Scop)

  • Antibiotics to treat infections

  • Corticosteroids to reduce inflammation and swelling

  • Antidepressants, such as drugs called selective serotonin or norepinephrine reuptake inhibitors (SSRIs or SNRIs) or amitriptyline (multiple brand names) or nortriptyline (Aventyl, Pamelor)

  • Medications to treat peripheral neuropathy

Pain management. You may have a variety of options to manage pain from nerve damage:

  • Pain medicines, including opioids

  • Nerve blocks and transcutaneous electric nerve stimulation (TENS), which provide pain relief

Rehabilitation. There are several health care professionals who can help you regain strength, physical functioning, and independence that may have been lost.

  • Occupational therapy to maintain motor skills needed for daily activities

  • Physical therapy to improve physical strength, balance, coordination, and mobility

  • Speech therapy to improve speech and learn ways to change speech as needed

  • Evaluation by a neuropsychologist to look at cognitive function

Changes at home. You may be able to make some changes at home to help keep you safe. Some suggestions include:

  • Installing hand rails in the bathroom

  • Using nonskid rugs

  • Adding extra lighting

  • Checking water temperature with an elbow instead of the hands

Related Resources

Understanding Chemotherapy

What is Radiation Therapy?