Pharmacokinetics of doxorubicin in man with induced acid or alkaline urine

The common side effects of doxorubicin (DOX) treatment, i.e. vomiting and diarrhoea, would be expected to alter the pharmacokinetics of DOX in man, the efficacy of treatment, and further aggravate the side effects through acid/base disturbances. The pharmacokinetics were therefore investigated in 4 anthracycline naive females with advanced mammary carcinoma in 2 series of DOX monotherapy 70 mg/m2 administered with an interval of 4 weeks between the treatments. Sequential loading either with acid or base was instituted 2 days before and continued for 2 days after DOX infusion. Median urine pH was 5.0 or 8.0, and median arterial blood pH 7.30 or 7.43 respectively. Plasma and urine samples were analyzed by high performance liquid chromatography (HPLC). No difference was seen between the acid and alkaline condition for DOX or doxorubicinol with regard to clearance from blood plasma, area under the curve, renal clearance, renal drug clearance/renal creatinine clearance. Thus moderate acid/base metabolic disturbances did not alter the pharmacokinetics of DOX up to 48 h after DOX infusion.