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Available clinical data on the use of oral ondansetron for the prevention of nausea and vomiting in patients undergoing cancer chemotherapy or surgery are reviewed. Injectable ondansetron hydrochloride is very effective in preventing nausea and vomiting associated with even the most emetogenic antineoplastic drugs. In December 1992, 4- and 8-mg oral tablets (ondansetron hydrochloride dihydrate) became available. Many of the clinical trials of oral ondansetron have not compared it with other antiemetics or have compared it only with placebo. Oral ondansetron has shown efficacy in such trials, but the standard of care for preventing chemotherapy-induced emesis is not placebo. Studies involving a prechemotherapy i.v. dose of ondansetron followed by oral therapy have shown high response rates for the whole study period; however, when day 1 is excluded, the results are not impressive for the remainder of the study period. It seems that the period beyond 24 hours is when oral ondansetron is effective, and that efficacy against acute emesis is due to i.v. ondansetron. Clinical trials in which oral ondansetron and oral metoclopramide were compared showed ondansetron to be, at best, equal to metoclopramide. One study showed the combination of dexamethasone and metoclopramide to be superior to oral ondansetron. Oral ondansetron is more effective than placebo in preventing post-operative nausea and vomiting in gynecologic surgery patients; however, there have been no comparative studies, and routine use of antiemetics in most surgical patients may be unnecessary because newer anesthetics are less emetogenic. Although the adverse effects of oral ondansetron are milder than those of standard antiemetics, this may not compensate for the drug's high cost. Oral ondansetron is not superior to traditional antiemetics for the prevention of nausea and vomiting caused by chemotherapy or surgery.

OBJECTIVE:To review the pathophysiology of hypertension and complications in patients with diabetes mellitus, specifically focusing on diabetic nephropathy; to evaluate the current clinical literature regarding the appropriate management of hypertension in this patient group; and to offer treatment recommendatiDATA SOURCES:A MEDLINE search of applicable English-language clinical studies, abstracts, and review articles pertaining to hypertension, diabetes, and diabetic nephropathy.STUDY SELECTION:Relevant studies on humans, examining hypertension, diabetes, and diabetic nephropathy, and the effects of drug therapy on these interrelated disease states.DATA SYNTHESIS:Pathophysiology of hypertension in the patient with diabetes mellitus and the pathophysiology of diabetic nephropathy are discussed. Studies evaluating the therapeutic effect of certain antihypertensive agents, their effect on glucose control and insulin sensitivity, and the progression of diabetic nephropathy are reviewed. Recommendations on the treatment of the patient with diabetes and hypertension are given.CONCLUSIONS:The treatment of the patient with diabetes mellitus and hypertension remains complex. Interventions in this patient population should not only decrease blood pressure, but also reduce the risk of both vascular and nonvascular complications. Data support the theory that by controlling a patient's hypertension, the incidence of albuminuria and the progression of diabetic nephropathy are slowed. Additionally, data are available to support the use of pharmacologic interventions in nonhypertensive patients with diabetes and proteinuria. Drug therapies that have produced reductions in proteinuria in this patient population include angiotension-converting enzyme inhibitors and nondihydropyridine calcium-channel antagonists. Additional information is needed to better differentiate the individual agents within each of the antihypertensive drug classes regarding their individual effects on the patient with diabetes and hypertension, specifically effects on diabetic nephropathy and its progression to endstage renal disease.

To the Editor. —We would like to commend Dr Gaasch 1 for his excellent review on heart failure due to systolic and diastolic dysfunction. However, he recommends that symptomatic diastolic dysfunction be treated with β-adrenergic blockers or calcium channel blockers (CCBs). While we generally agree with this recommendation, we believe that further clarification is warranted. In the article, the statement was made that "negative chronotropic agents that slow the heart rate are the preferred therapeutic agents" and we fully support this recommendation. However, in Table 2 and in the explanation of the table, the blanket statement is made that β-blockers or CCBs should be used to treat symptomatic left ventricular dysfunction with normal ejection fraction (diastolic dysfunction). 1 In diastolic dysfunction, there is impaired filling and reduced diastolic relaxation of the left ventricle due to increased stiffness. 2 Tachycardia can cause increased diastolic wall tension and may worsen diastolic heart