Cytosine arabinoside (or Cytarbine™) is an antimetabolic drug the toxicity of which is related to its active metabolite ARA-CTP. When this metabolite incorporates DNA, it blocks its synthesis.
The use of high dosage of cytosine arabinoside overcomes the resistance of leukaemia cells which are resistant to conventional dosage.
Cytosine arabinoside is indicated in the treatment of acute leukaemia: myelocytic acute leukaemia, secondary leukaemia and a few solid tumours.
It can also be used by intrathecal administration for treating leukaemia meningitis.
Only specific toxicities (or major toxicities) are described here. Other common chemotherapy toxicities are described in the chapter on chemotherapy toxicity.
Most often related to intrathecal treatment, the main symptoms may be paraplegia, blindness, cerebella disease or coma. The most severe disorders are observed in the case of concomitant irradiation of the central nervous system for leukaemia meningitis.