Temozolomide FAQs

TMZ is a type of chemotherapy drug called an alkylating agent. Alkylating agents add alkyl groups to DNA, disrupting its structure enough to cause damage and eventually killing the cell. Although TMZ cannot discriminate between healthy and cancerous cells, it is more harmful to cells that are growing quickly (like tumor cells). Other healthy cells in the brain do not divide as rapidly (some do not divide at all), and have enough time to repair the DNA damage caused by TMZ.

TMZ is particularly effective in treating brain tumors, because unlike many chemotherapy drugs, it can cross the blood-brain barrier (BBB). The BBB normally prevents harmful substances in the blood (like bacteria and toxins) from entering the brain, but also keep out a lot of chemotherapy drugs.

TMZ is currently approved for the treatment of adult patients with anaplastic astrocytoma (grade III) or glioblastoma (grade IV). TMZ is also used for adult patients with anaplastic oligodendrogliomas as well as grade II astrocytomas and oligodendrogliomas.

Ongoing clinical trials at UCSF are testing the efficacy of TMZ in combination with everolimus for treatment of a subset of patients with grade II astrocytomas and oligodendrogliomas.

TMZ is taken orally as a pill. The exact dose and schedule will be determined based on your individual treatment plan, depending on your diagnosis, overall health, and ongoing measures like complete blood counts (CBC).

When combined with radiation, TMZ is typically taken every day (Monday – Sunday) for 6-7 weeks. During this time, your blood counts will be measured at least every 2 weeks to monitor the effect of TMZ on your body. If blood counts get too low, you may be at risk for infection, anemia, and/or bleeding.

Other times, TMZ may be taken on an intermittent schedule; for example, daily for the first 5 days of a 28-day treatment cycle for several months in a row. Regardless, your neuro-oncologist will discuss the TMZ dose and schedule that is best for you.

Like all chemotherapy drugs, TMZ may cause side effects. Some of the most common side effects include the following:

• Nausea and vomiting
• Increased risk of infection
• Constipation
• Headache
• Fatigue
• Decreased appetite

These side effects are usually temporary and will cease after treatment is complete. However, during chemotherapy treatment, additional drugs may be prescribed to manage the side effects. For example, your doctor will prescribe an anti-nausea drug to take every day before you take the TMZ to prevent nausea and vomiting.

Seek emergency help and contact your health care provider immediately if any of the following uncommon symptoms occur:

• Fever of 100.4°F (38°C) or higher (possible sign of infection)
• Shortness of breath, wheezing, difficulty breathing, closing up of throat, facial swelling (possible allergic reaction)
• Rash (possible allergic reaction)

Tips for reducing nausea:

• Take medication as directed, on an empty stomach
• Eat small, frequent meals
• Take anti-nausea medication 1 hour before taking the TMZ

Tips for reducing infection:

• Wash your hands frequently
• Avoid crowds, or people with colds
• Contact your doctor if you have signs of infection (like fever)

Tips for reducing constipation:

• Stay hydrated, drinking 2-3 quarts of water per day (unless otherwise directed)
• If prescribed by your doctor, take stool softener medication

General Tips:

• Maintain good nutrition
• Get plenty of rest
• Stay active, but avoid overexertion or activities that could cause injury
• Contact your health care team if you have any additional questions