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Temozolomide Side Effects

The most commonly reported side effects of temozolomide include off label use, death, and disease progression, based on 22,795 FDA adverse event reports from 2004 to 2025. 5.5% of reports found the drug to be ineffective.

Temozolomide side effects

Percentages show how often each reaction appears relative to total reports for temozolomide.

1
Off Label Use7.9%1,790
2
Death7.7%1,746
3
Disease Progression7.4%1,691
4
Product Use In Unapproved Indication6.1%1,399
5
Thrombocytopenia5.7%1,291
6
Drug Ineffective5.5%1,249
7
Nausea5.4%1,235
8
Fatigue4.4%1,000
9
Neutropenia3.8%870
10
Vomiting3.6%815
11
Malignant Neoplasm Progression3.4%768
12
Diarrhoea2.9%651
13
Febrile Neutropenia2.9%651
14
Anaemia2.8%641
15
Seizure2.6%582

These are voluntary reports and do not establish that temozolomide caused these reactions.

Report severity

76.9%Serious17,529 reports
31.3%Hospitalizations7,136 reports
20.2%Fatal4,609 reports

Seriousness is determined by the reporter, not by OpenClaim.

Temozolomide drug interactions

Other drugs that appear in adverse event reports alongside temozolomide. Drugs flagged as a suspected cause appear in the first column. Drugs taken at the same time but not suspected appear in the second.

Also suspected

1
Bevacizumab10.5%2,384
2
Irinotecan-hydrochloride7.6%1,734
3
Etoposide5.7%1,300
4
Capecitabine5.4%1,236
5
Carboplatin4.3%977
6
Vincristine-sulfate4.2%956
7
Methotrexate4.0%917
8
Dexamethasone3.9%883
9
Cyclophosphamide3.7%838
10
Rituximab3.3%745
11
Ifosfamide3.0%680
12
Doxorubicin-hydrochloride2.3%525
13
Levetiracetam2.3%518
14
Cisplatin1.8%414
15
Ibrutinib1.8%409

Taken alongside

1
Dexamethasone10.4%2,374
2
Ondansetron8.2%1,867
3
Levetiracetam7.9%1,793
4
Acetaminophen4.8%1,097
5
Sulfamethoxazole3.9%888
6
Trimethoprim3.4%779
7
Pantoprazole-sodium3.1%699
8
Omeprazole2.9%666
9
Lorazepam2.3%517
10
Levothyroxine-sodium2.3%513
11
Atorvastatin-calcium2.2%491
12
Amlodipine2.0%461
13
Irinotecan-hydrochloride2.0%457
14
Prochlorperazine2.0%448
15
Capecitabine1.8%420

Co-occurrence in adverse event reports does not establish a drug interaction. Patients often take multiple medications, and these lists reflect prescribing patterns rather than causal relationships. Consult a healthcare provider about potential drug interactions.

Who reports temozolomide side effects

39.3% of temozolomide adverse event reports involve female patients and 46.5% involve male patients. The largest age group is adult at 61%. These figures reflect who reports side effects, not underlying risk.

Sex

Female39.3%
Male46.5%
Unknown14.2%

Age group

< 21.0%
2–117.8%
12–173.9%
18–6460.7%
65+26.7%

What is temozolomide used for

Conditions and purposes for which patients were taking temozolomide when the adverse event was reported.

Abdominal MassAbdominal NeoplasmAccidental Exposure To ProductAcquired Immunodeficiency SyndromeAcral Lentiginous MelanomaAcral Lentiginous Melanoma Stage IvActh-producing Pituitary TumourActh-producing Pituitary TumourAcute Kidney InjuryAcute Lymphocytic LeukaemiaAcute Myeloid LeukaemiaAdenoid Cystic CarcinomaAdenoma BenignAdenomatous Polyposis ColiAdjuvant Therapy

Showing 15 of 860 indications

Temozolomide brand names and reporting trend

Temozolomide is sold under the brand name Temozolomide.

Brand names

Temozolomide23,386

Quarterly reports (20042025)

20052010201520202025

An upward trend reflects increased FAERS reporting overall, not necessarily increased risk.

Taking temozolomide with another medication?

Ask OpenClaim about your specific drug combination. Get a sourced report using FDA data, drug labels, and medical literature.