From Dog

Lomustine is an alkylating nitrosourea compound used in chemotherapy.

This drug has a highly lipid soluble drug, and thus crosses the blood brain, allowing it to be used for CNS lymphoma in dogs.

Hepatotoxicity is a common side-effect with this drug, as well as neutropenia. A chronic dose-limiting side-effect is thrombocytopenia[1].

These affects can be mitigated to a degree by use of adjunctive medications S-Adenosylmethionine and silybin[2].

Reports of development of hemangioblastoma may preclude use of this drug in pregnant bitches[3].

Dexamethasone has been reported to be ineffective in attenuating the neutropenia caused by lomustine in dogs[4].

Recommended dose is 2.84 mg/m2 orally once for a period of 3 - 6 months[5].


  1. Kristal O et al (2004) Hepatotoxicity associated with CCNU (lomustine) chemotherapy in dogs. J Vet Intern Med 18:75–80
  2. Skorupski KA et al (2011) Prospective randomized clinical trial assessing the efficacy of Denamarin for prevention of CCNU-induced hepatopathy in tumor-bearing dogs. J Vet Intern Med 25(4):838-845
  3. Napalkov NP et al (1981) Transplacental carcinogenic effect of n-nitrosoethylurea in dogs. Cancer Lett 12(1-2):161-167
  4. Intile JL et al (2009) Evaluation of dexamethasone as a chemoprotectant for CCNU-induced bone marrow suppression in dogs. Vet Comp Oncol 7:69–77
  5. Tripp CD et al (2011) Tolerability of metronomic administration of lomustine in dogs with cancer. J Vet Intern Med 25(2):278-284