This medication is used to treat certain types of brain cancer. Temozolomide belongs to a class of drugs known as alkylating agents. It works by slowing or stopping the growth of cancer cells.

This section contains uses of this drug that are not listed in the approved professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.

This drug may also be used for other types of cancer (such as bone cancer).

Read the Patient Information Leaflet if available from your pharmacist before you start taking temozolomide and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth as directed by your doctor, usually once a day on a treatment schedule. Swallow the capsules whole with a full glass of water (8 ounces or 240 milliliters). Do not open, chew, or dissolve the contents of the capsules. If you vomit after taking your dose, do not take any more medication. Wait and take your next dose at the regular time. To reduce nausea and vomiting, take temozolomide on an empty stomach or at bedtime. For the best effect, take this medication at the same time every day in relation to a meal (for example, 1 hour before or 3 hours after a meal).

The dosage and treatment schedule are based on your medical condition, height, weight, and response to treatment. Carefully follow your doctor's directions for taking this medication. To help you remember, mark your calendar with a reminder.

Your doctor may also prescribe other medications (such as antibiotics) to help prevent infection or side effects. Follow your doctor's directions for taking all your medications.

Do not increase your dose or use this drug more often or for longer than prescribed. Your condition will not improve any faster, and your risk of serious side effects will increase.

If the capsules are accidentally opened or damaged, avoid inhaling the medication or getting it on your skin. If contact occurs, flush the area with water. Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the capsules.

Nausea, vomiting, loss of appetite, mouth sores, changes in taste, constipation, tiredness, dizziness, trouble sleeping, or headache may occur. Nausea and vomiting can be severe. In some cases, your doctor may prescribe medication to prevent or relieve nausea and vomiting. Eating several small meals, not eating before treatment, or limiting activity may help lessen some of these effects. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Temporary hair loss may occur. Normal hair growth should return after treatment has ended.

People using this medication may have serious side effects. However, you have been prescribed this drug because your doctor has judged that the benefit to you is greater than the risk of side effects. Careful monitoring by your doctor may decrease your risk.

Although temozolomide is used to treat cancer, it may rarely increase your risk of getting other cancers. Also, temozolomide decreases bone marrow function, an effect that may lead to a low number of blood cells such as red cells, white cells, and platelets. This effect can cause anemia, decrease your body's ability to fight an infection, or cause easy bruising/bleeding. Tell your doctor right away if you develop any of the following symptoms:

• unusual tiredness
• pale skin
• signs of infection (such as sore throat that doesn't go away, fever, chills)
• easy bruising/bleeding

Tell your doctor right away if you have any serious side effects, such as:

• symptoms of liver damage (such as stomach/abdominal pain, yellowing eyes/skin, dark urine)

Get medical help right away if you have any very serious side effects, such as:

• seizure

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, such as:

• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before taking temozolomide, tell your doctor or pharmacist if you are allergic to it; or to dacarbazine; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• kidney problems
• liver problems
• bleeding/blood problems

Temozolomide can make you more likely to get infections or may make current infections worse. Stay away from anyone who has an infection that may easily spread (such as chickenpox, COVID-19, measles, flu). Talk to your doctor if you have been exposed to an infection or for more details.

Tell your health care professional that you are using temozolomide before having any immunizations/vaccinations. Avoid contact with people who have recently received live vaccines (such as flu vaccine inhaled through the nose).

To lower the chance of getting cut, bruised, or injured, use caution with sharp objects like razors and nail cutters, and avoid activities such as contact sports.

This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).

Before having surgery, tell your doctor or dentist about all the products you use (such as prescription drugs, nonprescription drugs, and herbal products).

Women and older adults may be more sensitive to the side effects of this drug, especially increased risk of infection and easy bruising/bleeding.

Men should not donate sperm while using temozolomide and for 3 months after stopping this drug.

Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the capsules.

Tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while using temozolomide. Temozolomide may harm an unborn baby. Your doctor should order a pregnancy test before you start this medication. Women using this medication should ask about reliable forms of birth control during treatment and for 6 months after the last dose. Men using this medication who have a partner that is pregnant or who can become pregnant should use condoms for birth control during treatment and for some time after the last dose. If you or your partner becomes pregnant, talk to your doctor right away about the risks and benefits of this medication.

It is unknown if this drug passes into breast milk. Because of the possible risk to the infant, breastfeeding is not recommended while using this drug and for 1 week after the last dose. Consult your doctor before breastfeeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (such as prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others.

Lab and/or medical tests (such as complete blood count, liver function, brain scan) should be done before you start taking this medication and while you are taking it. Keep all medical and lab appointments.

It is important to take each dose of this medication as scheduled. If you miss a dose, ask your doctor or pharmacist right away for a new dosing schedule. Do not double the dose to catch up.

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

Your condition can cause complications in a medical emergency. For information about enrolling in MedicAlert, call 1-888-633-4298 (US) or 1-800-668-1507 (Canada).