Acute Hypotension after Loxoprofen Sodium Co-administration in Two Acute Myeloid Leukemia Patients Undergoing Chemotherapy Treatment.

A 55-year-old female had been treated for acute myeloid leukemia (AML) since 1998. In November 2001, she entered a hospital to undergo medical treatment. Her blood pressure at the time of hospitalization was 110/ 78 mmHg. Radiotherapy was carried out and therefore chemotherapy with cytarabine and mitoxantrone was started. Loxoprofen sodium (LOX) was prescribed for a fever which developed during the treatment. After taking LOX, dizziness and perspiration appeared, and the patient's blood pressure declined to 74/47 mmHg.A 40-year-old female had received chemotherapy for the treatment of AML since June 2001. Her blood pressure was 118/74 mmHg and pulse was regular at the time of hospitalization. The electrocardiogram findings were normal. Although myelosupression was remarkable and arrhythmia was observed during the course of therapy, chemotherapy was continued. Chemotherapy with aclarubicin, cytarabine and mercaptopurine was started, and LOX was prescribed for a fever during the treatment. After taking LOX, the patient's systolic blood pressure declined 24 mmHg.In both cases, hypotension was observed 2 to 3 hours after the administration of LOX and it was repeatedly observed after every administration of LOX. The observed cardiac abnormality was considered to be due to residual chemotherapy remaining in the cardiac muscle. We consider that hypotension developed due to some influence on heart function by both the augmentation of the action of LOX and its active metabolite (LOX-OH) due to hypoalbuminemia and increased total body fluid level through the repression of prostaglandin synthesis in the kidney. As a result, the careful monitoring of blood pressure is necessary when co-administrating LOX with chemotherapy in patients with hypoalbuminemia.