Purpose. While chemotherapy-related toxicities affect cancer patients' activities of daily living and result in large expenditures of medical care for treatment, few studies have assessed the out-of-pocket and indirect costs incurred by patients who experience toxicity. The objective of this study was to evaluate the feasibility of obtaining detailed and comprehensive cost information from patients who experienced neutropenia, thrombocytopenia, or neurotoxicity during treatment. Methods. Ovarian cancer patients who experienced chemotherapy-associated hematologic or neurologic toxicities were asked to record detailed information about hospitalization, laboratories, physician visits, phone calls, home visits, medication, medical devices, lost productivity, and caregivers. Resource estimates were converted into cost units, with direct medical cost estimates based on hospital cost-accounting data and indirect costs (i.e., productivity loss) on modified labor force, employment, and earnings data. Results. Direct medical costs were highest for neutropenia (mean of $7,546/episode), intermediate for thrombocytopenia (mean of $3,268/episode), and lowest for neurotoxicity (mean of $688/episode). Indirect costs relating to patient and caregiver work loss and payments for caregiver support were substantial, accounting for $4,220, $3,834, and $4,282 for patients who developed neurotoxicity, neutropenia, and thrombocytopenia, respectively. The total costs of chemotherapy-related neurotoxicity, neutropenia, and thrombocytopenia were $4,908, $11,830, and $7,550. Conclusion. Our study has shown that, with the assistance of patients who are experiencing toxicity, estimation of the total costs of cancer-related toxicities is feasible. Indirect costs, while not included in prior estimates of the costs of toxicity studies, accounted for 34% to 86% of the total costs of cancer supportive care.