Temozolomide

Introduction

Temozolomide is a chemotherapy drug used for treating a type of brain tumor (glioblastoma) which is normally fatal.

Uses For

Temozolomide is mainly used to treat glioblastoma, a type of brain tumor, which is otherwise usually fatal. It is also used to treat advanced melanoma, a type of skin cancer.

Mechanism of Action

Temozolomide works by inhibiting the enzymes that repair DNA damage. This makes cells more vulnerable to the effects of chemotherapy as they can no longer repair themselves. It also increases sensitivity to radiation therapy. By stopping the cells from repairing themselves, the body is able to break down the cancerous cells.

How Long Does it Take to Work?

It typically takes between four and six weeks for Temozolomide to start working. During this time the patient will receive regular scans to monitor progress.

Absorption

Temozolomide is rapidly and completely absorbed following oral administration. It is absorbed via the small intestine, with peak concentration occurring around three hours after ingestion.

Route of Elimination

Temozolomide is eliminated from the body primarily via the liver and excreted in the urine.

Dosage

Newly Diagnosed GBM: 75 mg/m² for 42 days concomitant with focal radiotherapy followed by initial maintenance dose of 150 mg/m² once daily for Days 1-5 of a 28-day cycle of Temozolomide for 6 cycles.

Refractory Anaplastic Astrocytoma: Initial dose 150 mg/m² once daily for 5 consecutive days per 28-day treatment cycle.

The standard dose for Temozolomide is 200 mg/m2/day. This dose is usually taken orally for five consecutive days, followed by a 23-day break. The dose may be adjusted depending on the patient's individual tolerance. The maximum recommended dose is 200 mg/m2/day.

Administration

Temozolomide is usually taken orally, either as a capsule or as a liquid suspension. It is usually taken with food to help reduce nausea and other side effects.

Side Effect

Common side effects of Temozolomide include nausea, vomiting, fatigue, loss of appetite, constipation, diarrhea, hair loss, skin changes, headache, dizziness, and confusion.

Toxicity

Temozolomide has been associated with a range of toxicities including myelosuppression, which is a reduction in the number of circulating blood cells, and neurotoxicity, which can affect the peripheral and central nervous system.

Precautions

Temozolomide should be used with caution in patients with pre-existing hematological abnormalities, cardiac abnormalities, or hepatic or renal impairment. It is also important to monitor for signs of toxicity, including changes in blood cell counts, during treatment.

Interaction

Certain drugs can interact with Temozolomide and increase the risk of toxicity. These include certain antibiotics, anticonvulsants, corticosteroids, and chemotherapeutic agents.

Disease Interaction

Temozolomide should be used with caution in the presence of certain diseases and conditions. These include hepatic or renal impairment, bone marrow suppression, and cardiac arrhythmias.

Drug Interaction

Certain drugs can interact with Temozolomide and increase the risk of toxicity. These include certain antibiotics, anticonvulsants, corticosteroids, and chemotherapeutic agents.

Food Interactions

Food does not interact with Temozolomide , however it is important to take the medication with food so as to reduce the risk of nausea and vomiting.

Pregnancy Use

Temozolomide is not recommended for pregnant women as it may harm the unborn baby. Women who are pregnant or plan to become pregnant should tell their doctor before taking Temozolomide .

Lactation Use

It is not known if Temozolomide passes into breast milk or if it could harm a nursing infant. Women who are breast-feeding should tell their doctor before taking Temozolomide .

Acute Overdose

Symptoms of an acute overdose of Temozolomide may include drowsiness, confusion, nausea, vomiting, and seizures. Treatment of an overdose of this medication is symptomatic and supportive and should be done in a hospital setting.

Contraindication

Temozolomide is contraindicated in patients with hypersensitivity to it, other alkylating agents, or any other components of the product.

Use Direction

Temozolomide should be taken exactly as prescribed by the doctor. The capsules should be swallowed whole, not crushed, chewed, or opened. It is important that the patient adheres to the prescribed dose and schedule.

Storage Condition

Temozolomide should be stored in a dry place at room temperature. It should not be frozen and should be kept away from light. It should be kept away from children.