Chemo-Induced Seizures

Description: A seizure is a sudden attack, spasm or convulsion. Your body and brain function in the presence of electrical impulses, or activity. During a seizure, a sudden, abnormal, electrical wave of activity may "misfire", causing you to "twitch", or "jerk". This twitching may be mild, or it may be more exaggerated. Seizures have multiple causes, which may include certain chemo treatments.

• A seizure may last seconds to minutes, each episode.
• Seizure activity may not be very predictable. You may have an aura or hallucinations before you have a seizure, but many people do not.
• You may have a seizure, and then you may never have one again.

Symptoms:

• You may notice twitching and jerking of one or all parts of your body. This twitching is uncontrolled, and involuntary. You may notice this in your hand, foot, arms, or legs especially.
• You may experience a muscle spasm that may spread through your body. You may lose consciousness.
• You may have hallucinations, or see things that may not be present or real. These may include auditory (which means, that you hear sounds), or visual (you see things that aren't real) hallucinations.
• Some people have an "aura" before their seizures. An aura is a feeling that you notice before the seizure begins. You may notice different smells (like burning toast), or certain noises. You may still have a seizure, without an aura.
• You may be unable to control your bladder. You may wet or soil yourself.
• After a seizure, you may feel "disoriented", or drowsy.

Seizures are a sign that there may be an underlying disease or problem, affecting your brain wave activity. Chemotherapy itself does not cause seizures but may cause conditions that put a person at increased risk of seizure for example: dehydration from uncontrolled nausea and vomiting.

You may be at risk for a seizure if:

• You have been diagnosed with cancer of the brain or central nervous system.
• You have had a recent trauma or injury to your head.
• You may have low blood sodium levels, or other electrolyte imbalances in your blood.
• You have infection in your brain or central nervous system, such as meningitis.
• You have had a stroke, or loss of blood supply to the brain.
• You are experiencing withdrawal from alcohol or drugs, or you are currently intoxicated by alcohol or drugs.
• Intrathecal or intravesical administration of chemotherapy. The medication is given directly into the spinal cord or brain.
• Some high-doses of chemotherapy agents (such as busulfan for bone marrow transplantation). The risk of chemo-induced seizures usually resolves when you are finished taking the medication.

It is important to treat the underlying cause of seizures, whether it is due to medications, illness, or a disease state. To diagnose what has caused a seizure, your healthcare provider may order certain blood tests, and radiology studies. These may include a CT scan or MRI of your brain, or an EEG to measure your brain wave activity. (See "common examinations" for a description of each).

Symptom Management:

Things you can do (the patient):

Prevention:

• I you are at increased risk of seizure you would want to do what you can to decrease risks under your control for example:
• Take anti-seizure medications as prescribed. Certain anti-seizure medications may be more effective if the levels are "good", or "therapeutic" in your blood stream. Your doctor or healthcare provider may order blood tests periodically to see what the level of medication is in your blood.
• Do not become over-tired, make sure to get enough sleep at night.
• Contact your health care professional if you are experiencing uncontrolled side effects of chemotherapy such as vomiting, or diarrhea in which you are at risk of dehydration or electrolyte imbalances.
• If you have had a seizure - either chemo-induced or not - avoid alcohol, drugs and medications that may interfere with your anti-seizure medication.

Safety:

• If you have a history of seizures, or think that you may be at risk for a seizure due to your disease, it is important to discuss the signs and symptoms of a seizure with your friends, family, and close contacts (including your co-workers). Also, it may be helpful for you and them, to be aware of what you should do during a seizure. If you are having a seizure:
• Make sure that the clothing around your neck is loosened. You may do this yourself, or have your friends or family members assist you.
• Tell them that you should not be moved during a seizure, unless you are at immediate risk of injuring yourself. You will have little control over your actions during a seizure, and you may become injured, or injure someone else. Instead, try to move the things around you.
• You should not be held down during a seizure. You should be able to move freely. Instruct your friends and family to move out of contact with you.
• If you are vomiting, try to turn your head to the side. This will prevent you from swallowing your secretions, and perhaps, choking.
• Do not allow anyone to put anything in your mouth. Many people think that you must put something in your mouth to protect your tongue from injury. In fact, you may be more at risk for inhaling what is placed in your mouth, than swallowing your tongue.
• Have someone write down how long the seizure is lasting. If the seizure is prolonged, lasting for 3 to 5 minutes, make sure that they check to see if you are breathing.
• As always, if there is a concern for your safety, if is important to seek emergency assistance by calling 911.

Living with seizures:

• Wear a "medic alert" bracelet at all times, which will notify someone that you have a history of seizures, if you are alone.
• Do not perform risky activities, such as scuba diving, or motor biking, if you have a history of seizures. Also avoid working with heavy machinery, if possible. Instead, try to participate in other hobbies or activities that will not put you at risk if you have a seizure.
• If you have had a seizure, you should not drive a car, or operate any type of heavy machinery, unless you have been seizure free for 6 months. You must always have your doctor or healthcare provider "clear" you for performing such activities before you do them.
• If you are still smoking, you should quit. Discuss with your healthcare provider techniques that can help you quit.
• Participating in support groups may be helpful to discuss with others what you are going through. Ask your healthcare provider if he or she is aware of any support groups that would benefit you.
• Try to exercise, as tolerated, to maintain your optimal level of functioning. Make a daily walk with a friend or a family member a part of your routine. Even light walking may help you to promote the flow of oxygen in your lungs and blood (oxygenation), which will help you feel better.

Drugs That May Be Prescribed By Your Doctor:

Treatment of chemo-induced seizures and seizure related activity is based on the underlying cause. For example:

• If the seizures are due to cancer chemotherapy, radiation therapy, surgery and steroids may be beneficial.
• If you have an infection, antibiotics will most likely be used.
• If the seizure is due to electrolyte imbalances in your blood stream, these will be corrected.

You may or may not be placed on anti-seizure medication if you have cancer in your brain, unless you have had a seizure. Your doctor will determine this.

You may be admitted to the hospital for treatment and observation.

Anticonvulsants - There are many types of anticonvulsants, or anti-seizure drugs available. These include older and well-studied drugs, such as phenytoin (Dilantin®); or newer drugs, such as levetiracetam (Keppra®).

• Many drugs can interfere with the way some of the anticonvulsant drugs are absorbed, be sure to discuss all prescription and over-the-counter medications, as well as any herbal products that you may be taking with your health care professional.
• Antacids may change the way many anti-seizure medications are absorbed. Do not take antacids within 2 hours of your anti-seizure medications. If you have any questions, ask your healthcare provider.

Corticosteroids: Corticosteroids work by decreasing inflammation (swelling) in many areas of the body. You may be taking steroids if you have cancer that has spread to your brain. The swelling in the areas where the tumors are located could be causing your seizures.

If you believe you are suffering from chemo-induced seizures, the following guidelines suggest when to call your doctor or health care provider:

• Seek emergency assistance immediately, if you stop breathing during a seizure.
• If you have a seizure.
• If seizures are common for you contact your health care provider if they begin to increase in number, worsen or are prolonged.
• Fever of 100.5° F (38° C), chills, sore throat (possible signs of infection if you are receiving chemotherapy).
• If you feel more confused and forgetful than usual.