Delayed Myelosuppression and Risk of Overdosage

• Delayed Myelosuppression

Gleostine causes myelosuppression including fatal myelosuppression. Myelosuppression is delayed, dose-related, and cumulative; occurring 4 to 6 weeks after drug administration and persisting for 1 to 2 weeks. Thrombocytopenia is generally more severe than leukopenia. Cumulative myelosuppression from Gleostine is manifested by greater severity and longer duration of cytopenias. Monitor blood counts for at least 6 weeks after each dose. Do not give Gleostine more frequently than every 6 weeks .

• Risk of overdosage

PRESCRIBE, DISPENSE, AND ADMINISTER ONLY ENOUGH CAPSULES FOR ONE DOSE. Fatal toxicity occurs with overdosage of Gleostine. Both physician and pharmacist should emphasize to the patient that only one dose of Gleostine is taken every 6 weeks.