Zolomide

Indications

Temozolomide is an oral chemotherapy medicine used to treat certain brain tumours. It is used in adults with newly diagnosed glioblastoma (together with radiotherapy and then on its own), and in adults and children with malignant glioma, such as glioblastoma or anaplastic astrocytoma, that has come back or got worse after other treatment. Doctors may also use it for some other cancers, such as advanced melanoma.

How It Works

Temozolomide is an alkylating agent. In the body it changes into an active substance that attaches small chemical groups (methyl groups) to the DNA of cancer cells. This damages the DNA so the cells cannot divide and they die. It can cross into the brain, which makes it useful for brain tumours.

Dosage and Administration

The dose is calculated by your cancer specialist from your body surface area and blood counts; take it exactly as prescribed. It is usually taken once a day on an empty stomach, at least one hour before a meal, at the same time each day, often in cycles (for example 5 days of treatment followed by a 23 day break). Swallow capsules whole with water; do not open, crush or chew them. Anti sickness medicine is often taken before each dose.

Interactions

Valproic Acid (Sodium Valproate) may slightly reduce its clearance. Other medicines that suppress the bone marrow increase the risk of low blood counts. Live vaccines should be avoided during treatment. Tell your doctor about all medicines and herbal products.

Contraindications

• Allergy to Temozolomide or Dacarbazine.
• Severe bone marrow suppression (very low white cells or platelets).
• Breastfeeding.

Side Effects

Common effects are nausea, vomiting, constipation, tiredness, loss of appetite, headache, hair thinning, rash and low blood counts, which increase the risk of infection, bleeding and anaemia. Liver tests may change.

Get urgent medical help if you have fever of 38°C or more, chills or other signs of infection, unusual bleeding or bruising, blood in urine or stools, severe or persistent vomiting, breathlessness or dry cough (possible lung infection or inflammation), yellow skin or eyes, or a severe skin reaction.

Pregnancy and Lactation

Temozolomide can harm an unborn baby. Women should avoid pregnancy and use effective contraception during treatment and for at least 6 months after the last dose; men should use contraception during treatment and for at least 3 months after. It may reduce fertility, so ask about sperm or egg preservation before starting. Do not breastfeed during treatment.

Precautions and Warnings

Blood counts are checked regularly, and treatment is delayed or reduced if they are low. People receiving it with radiotherapy are often given an antibiotic to prevent Pneumocystis pneumonia. Liver tests are monitored. There is a small risk of other cancers, such as leukaemia, later on. Handle capsules carefully, wash hands after touching them, and keep them away from others, especially pregnant women and children. Do not drive if you feel tired or dizzy.

Overdose

Overdose can cause severe low blood counts and infection. Seek emergency medical help immediately; blood counts will be monitored and supportive care given.

Therapeutic Class

Antineoplastic (anticancer) agent; alkylating agent (imidazotetrazine).

Storage

Store below 30°C in a dry place, away from light and out of the reach of children. Keep in the original container, tightly closed.