USMLE

Nitrosoureas

3,941 views
Oncology Pharm
  1. Bleomycin
  2. Dactinomycin, Actinomycin D
  3. Doxorubicin, Daunorubicin
  4. Azathioprine, 6-MP
  5. Cladribine
  6. Cytarabine
  7. Busulfan
  8. Cyclophosphamide, Ifosfamide
  9. Nitrosoureas
  10. Paclitaxel
  11. Vincristine, Vinblastine
  12. Cisplatin, Carboplatin, Oxaliplatin
  13. Etoposide, Teniposide
  14. Irinotecan, Topotecan
  15. Bevacizumab
  16. Erlotinib
  17. Cetuximab, Panitumumab
  18. Imatinib, Dasatinib
  19. Rituximab
  20. Bortezomib, Carfilzomib
  21. Trastuzumab
  22. Dabrafenib, Vemurafenib
  23. Raloxifene and Tamoxifen
  24. Hydroxyurea
  25. Procarbazine

Summary

The nitrosoureas carmustine and lomustine are alkylating agents that crosslink DNA after being bioactivated by P450 enzymes in the liver. These drugs have a unique ability to cross the blood-brain barrier, making them useful for treating brain tumors, but this ability can also lead to CNS toxicity in patients taking these medications. 

Key Points

  • Nitrosoureas
    • Drugs
      • Carmustine
      • Lomustine
    • Mechanism
      • Crosslinks DNA
        • Requires bioactivation by liver (P450)
        • Crosses blood-brain barrier (BBB) into the CNS
    • Clinical Use
      • Brain tumors
        • Because it crosses BBB
        • Including glioblastoma multiforme 
    • Adverse Effects
      • CNS toxicity
        • Symptoms including ataxia, convulsions, dizziness