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Diabetic nephropathy is a complication of type 1 and type diabetes mellitus and the leading cause of end-stage renal disease in the United States. The health care system spends billions of dollars every year to treat end-stage renal disease patients. Health care providers must address diabetic nephropathy. The American Diabetes Association set forth recommendations for early detection to slow the progression of renal disease and treatment guidelines for patients with diabetes along with hypertension and diabetic nephropathy. Routine screening and treatment are the key to ending the trend of patients with diabetic nephropathy progressing to end-stage renal disease. Glycemic and blood pressure control is important for managing diabetic nephropathy. Angiotensinconverting enzyme inhibitors and angiotensin receptor blockers have become drugs of choice for treating diabetic nephropathy, based on clinical studies showing they slow the progression of renal disease. Whether protein restrictions are necessary in patients with diabetic nephropathy is being debated.

Hemodialysis is a life-sustaining chronic therapy for individuals with end stage renal disease (ESRD). It is also frequently used for days to weeks for patients with acute renal failure who are awaiting the recovery of their kidneys from the acute toxic or traumatic event. Both populations of patients often require complex pharmacotherapeutic regimens, and it is not uncommon for them to be receiving 10 or more concomitant medications. Optimization of care for these patients is dependent on the selection of the most appropriate drug as well as dosage regimen design, which accounts for the influence of hemodialysis therapy on drug disposition. During the last 10 to 15 years there have been several significant changes in the prescribed dose of dialysis and the composition and size of dialyzers available for use. Furthermore, reuse of dialyzers, which was rare in the early 1980s, is now common; it is employed with over 70% of patients with ESRD. The new synthetic dialyzers, which are now used for over 60% of ESRD patients in the United States, are uniformly associated with dramatic improvements in drug removal; dialysis clearance increases of 3 to 10 fold were common for the few drugs evaluated. The influence of these changes in hemodialysis therapy on drug disposition are discussed in a quantitative fashion, and a conceptual framework for drug therapy regimen decision making is presented. For the majority of the drugs reviewed, however, there were no data in the literature regarding dialyzability with currently available dialyzers. The generation of dialyzability data for old and new pharmacotherapeutic agents with state of the art dialysis procedures is clearly needed.

Chronic kidney disease (CKD) is a progressive process leading to end stage renal disease and either dialysis or transplantation. Patients with CKD often have numerous comorbid conditions such as diabetes, hypertension, and acid-base and electrolyte disorders that can lead to alterations in homeostasis. Changes in drug disposition including hepatic metabolism via phase 1 (ie, cytochrome P-450 enzymes) and phase 2 (ie, conjugation) pathways have been reported. Biotransformation of drugs and endogenous substances within the kidney itself may also be compromised in the presence of CKD. Reduced hepatic and renal clearance leads to systemic accumulation of the parent drug as well as active and toxic metabolites. Characterization of specific hepatic cytochrome (CYP) enzyme pathways in patients with CKD is an area of current research and will lead to an understanding of phenotypic and genotypic expression patterns of several key drug-metabolizing enzymes. The evolving knowledge of CYP enzymes and the alterations that can occur in CKD should allow clinicians to predict adverse consequences of drug therapy and thus prevent these events from occurring. The pharmacy practitioner can also provide important pharmacotherapy interventions in this special patient population, including dose individualization, therapeutic drug monitoring, and evaluation of therapeutic outcomes.

Outpatient dialysis centers are a prime environment for clinical pharmacy intervention. Opportunity abounds for patient outcome-focused intervention such as intensive compliance counseling, drug-interaction screening, evaluation and interpretation of drug level assays, teaching (staff, physicians, patients), and enhanced overall medication management. Nephrology pharmacy is a relatively underdeveloped specialty practice, with clinical pharmacy practice in outpatient dialysis centers comprising a very small segment of that practice. There are many topics of concern that show a need for further evolution of this practice: polypharmacy, patient compliance, expensive medications (ie, recombinant human erythropoietin [rHuE-PO]), and Medicare End Stage Renal Disease (ESRD) program reimbursement constraints. In this report the origin and current status of the pharmacy nephrology service at St. Joseph Hospital and Health Care Center in Tacoma, WA is described.