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Pronunciation: tem-o-dar
Generic name: temozolomide
Dosage forms: oral capsules, injection for infusion
Drug class: Alkylating agents

Medically reviewed by Carmen Pope, BPharm. Last updated on Sep 20, 2023.

What is Temodar?

Temodar (temozolomide) is an alkylating agent that may be used to treat certain types of brain tumors in adults, specifically glioblastoma multiforme and anaplastic astrocytoma. It is used for:

Temodar first has to undergo conversion in the body to its active metabolite 5-(3-methyltriazen-1-yl)-imidazole-4-carboxamide (MTIC) to be active. The anti-cancer activity of MTIC is thought to be mainly due to the addition of alkyl groups to specific bases (mainly at the O6 and N7positions of guanine) which causes the DNA double-strand to break and results in cell death.

Temodar was first FDA-approved on August 11, 1999.


You should not take Temodar if you are allergic to temozolomide or to another cancer medication called dacarbazine.

Taking Temodar may increase your risk of developing certain types of bone marrow cancer. Talk with your doctor about your risk, which may be higher in seniors and females. Your doctor will monitor your blood counts during treatment and before each cycle.

Fatal and severe liver toxicity has been reported with Temodar. Your doctor will perform liver function tests before you start treatment and at various times thereafter.

Temodar increases your risk of developing Pneumocystis Pneumonia (PCP) and lymphopenia (very low levels of lymphocytes). The risk is higher if you are also taking steroids. Your healthcare provider will monitor you for these conditions.

Temodar increases your risk of myelodysplastic syndrome and secondary cancers including myeloid leukemia.

Females of reproductive potential should use effective contraception while taking Temodar because it can cause harm to the fetus. Male patients with pregnant partners or female partners of reproductive potential should use condoms.

Do not open a capsule, or use a capsule that has been accidentally broken. The medicine from a crushed or broken pill can be dangerous if you accidentally inhale it, or if it gets in your eyes, mouth, or nose, or on your skin. If this occurs, wash your skin with soap and water or rinse your eyes with water. Ask your doctor or pharmacist how to safely handle and dispose of a broken capsule. Swallow the capsules whole with a glass of water.

Before taking this medicine

You should not use Temodar if you are allergic to temozolomide or dacarbazine.

To make sure Temodar is safe for you, tell your doctor about all your medical conditions and if you have ever had:


Temozolomide can harm an unborn baby if the mother or the father is using this medicine. If you are a woman, you may need a pregnancy test to make sure you are not pregnant. Use birth control while using this medicine and for at least 6 months after your last dose. Tell your doctor right away if you inadvertently become pregnant.

If you are a man, use a condom for birth control if your sex partner can get pregnant. Keep using birth control for at least 3 months after your last dose. Do not donate semen during treatment and for 3 months after your last dose of Temodar. Tell your doctor right away if a pregnancy occurs.

It may be harder for a man to get a woman pregnant while using this medicine. You should still use birth control to prevent pregnancy because the medicine can harm an unborn baby.


Do not breastfeed while using this medicine, and for at least 1 week after your last dose.

How should I use Temodar?

Temodar is available as a capsule which can be self-administered or an intravenous injection which is given by a health care provider.

Temodar capsules

Take Temodar exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets.

The dosing schedule your doctor gives you depends on the type of brain cancer tumor that you have. Examples of dosing schedules include:

Your healthcare provider may change your dose of Temodar, or tell you to stop it for a short period or permanently if you have certain side effects.

Temodar injection

Your healthcare provider will administer Temodar for injection as an infusion directly into your vein over about 90 minutes.

Your healthcare provider may prescribe medicine to prevent or treat nausea, or other medicines to help relieve side effects.

What happens if I miss a dose?

Call your doctor for instructions if you miss a dose of Temodar. If you vomit shortly after taking the medicine, do not take another capsule until your next regularly scheduled dose.

What happens if I overdose?

If you take more Temodar than prescribed, call your healthcare provider or seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using Temodar?

Avoid being near people who are sick or have infections. Tell your doctor at once if you develop signs of infection.

Men should not donate semen while using Temodar and for at least 3 months after the last dose.

Avoid activities that may increase your risk of bleeding or injury. Use extra care while shaving or brushing your teeth.

What are the side effects of Temodar?

Temodar can cause serious side effects.

Get emergency medical help if you have signs of an allergic reaction to Temodar such as hives; difficulty breathing; or swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

Common side effects that affect 20% or more of people taking Temodar include:

Other side effects that may occur with the injection include:

Temodar can affect fertility in males and may affect your ability to father a child. Talk with your healthcare provider if fertility is a concern for you.

Tell your healthcare provider about any side effect that bothers you or that does not go away.

These are not all the possible side effects of TEMODAR. For more information, ask your healthcare provider or pharmacist. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088

What other drugs will affect Temodar?

Tell your doctor about all your other medicines, especially:

This list is not complete. Other drugs may interact with temozolomide, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.


Store capsules at room temperature 68°F to 77°F (20°C to 25°C) away from moisture and heat.

Keep out of the reach of children.


Temodar capsules

Temodar injection


 Merck Sharp & Dohme LLC.


  1. Product Label

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.