What are the precautions for taking Temozolomide?

In clinical studies of temozolomide , warnings and precautions such as bone marrow suppression, hepatotoxicity, pneumocystis pneumonia, secondary malignancies, embryo-fetal toxicity, and exposure to opened capsules have emerged.

1. Myelosuppression: including pancytopenia, leukopenia and anemia, some of which have fatal consequences. In trials, myelosuppression usually occurs during the first few cycles of treatment and is usually not cumulative. Perform a complete blood count and monitor ANC and platelet counts before initiating treatment and as clinically indicated during treatment. When temozolomide is used concomitantly with radiation therapy, obtain a complete blood count before initiating treatment, weekly during treatment, and as clinically indicated. For severe myelosuppression, discontinue temozolomide and continue at the same or reduced dose, or permanently discontinue temozolomide, as appropriate.

2. Hepatotoxicity: Fatal and severe hepatotoxicity has been reported in patients receiving temozolomide. Liver examinations were performed at baseline, midway through the first cycle, before each subsequent cycle, and approximately 2-4 weeks after the last dose of temozolomide.

3. Pneumocystis pneumonia (PCP): Patients receiving steroids or long-term temozolomide treatment are at increased risk of developing PCP. For patients with newly diagnosed glioblastoma, offer PCP prophylaxis to all patients during the concomitant phase. Continue PCP prophylaxis in patients who develop lymphopenia until remission to grade 1 or less. Monitor all treated patients for the emergence of lymphopenia and PCP.

4. Secondary malignant tumors: The incidence of secondary malignant tumors is increased in patients treated with temozolomide-containing regimens. Cases of myelodysplastic syndromes and secondary malignancies (including myeloid leukemia) have been observed following the use of temozolomide.

5. Embryo-Fetal toxicity: According to the results of animal studies and its mechanism of action, temozolomide taken by pregnant women can cause harm to the fetus. Adverse developmental outcomes have been reported in both pregnant patients and the pregnant partners of male patients. Oral administration of temozolomide during organogenesis in rats and rabbits resulted in embryonic lethality and multiple malformations at doses below the maximum human dose based on body surface area.

(1)Females: It is recommended that women of reproductive potential use effective contraceptive measures during treatment with temozolomide and within 6 months after the last dose; women are advised not to breastfeed during treatment with temozolomide and within 1 week after the last dose.

(2)Males: Due to potential genotoxic effects on sperm, it is recommended that male patients receive temozolomide during treatment and after the last doseDo not donate semen for 3 months; advise male patients with a female partner of reproductive potential to use condoms during treatment with temozolomide and for 3 months after the last dose.

6. Exposure to opened capsules: Patients are advised not to open, chew, or dissolve the contents of temozolomide capsules. Swallow the capsule whole with a glass of water. If capsule is damaged, avoid contact of powder contents with skin or mucous membranes. If contact with powder occurs, wash affected area immediately with water. If temozolomide capsules must be opened or the contents dissolved, this should be done by professionals trained in the safe handling of hazardous drugs using appropriate equipment and safety procedures.