Side effects of Temozolomide (TMZ)

Temozolomide is used to treat certain types of brain tumors. Temozolomide is in a class of medications called alkylating agents. It works by slowing or stopping the growth of cancer cells in your body.

Temozolomide (TMZ) is a chemotherapy drug that has been shown to improve average survival rate for people with some high grade brain tumours. 

Temozolomide (pronounced tee-mo-zol-oh-m-ide) is a type of chemotherapy drug that's approved for the treatment of glioblastomas and anaplastic astrocytomas.

Common side-effects

In some cases, TMZ can cause more serious side-effects. You should tell your oncologist immediately if you experience any symptoms, such as a sore throat or high temperature.

Low platelet count

TMZ treatment can cause a low platelet count. Platelets help the blood clot, so a low platelet count can significantly increase the risk of bleeding.

If the results of blood tests show a low platelet count, your doctor might consider delaying your treatment or reducing your dose.

In rare cases, TMZ can cause a more serious blood condition known as pancytopenia. Pancytopenia is when red and white blood cells, as well as platelets, are lower than normal. In such cases, you might receive blood and platelet transfusions (injections of blood) and G-CSF support (injections which help boost your immunity).

Loss of fertility

TMZ can, in some cases, cause infertility in men or women. Before starting treatment with TMZ, your doctor should discuss available options for preserving your fertility with you. If relevant, your doctor will also discuss with you effective birth control methods (contraception), as TMZ may also cause birth defects.

Pneumonia

If you’re being treated with TMZ, you have an increased risk of developing a type of pneumonia known as pneumocystis jirovecii pneumonia (PCP).

This is an infection of the lungs, caused by a fungus that’s common in the environment. It can cause infection in people with weakened immune systems. For this reason, your oncologist may prescribe a preventative antibiotic to reduce your chance of getting this infection.

Temozolomide is a prodrug that acts as a molecular delivery device to transport a reactive methylating species to guanine-rich sequences in the major groove of DNA. It is a quintessential “small molecule” of MW 194: every atom in the structure has a role in engineering its favorable chemical, pharmaceutical, and biological profile—ease of synthesis, acid stability, oral bioavailability, freedom from first-pass metabolism, transmission across the blood–brain barrier, and an acceptable toxicological profile unusual for a cytotoxic agent.