At a time when the acquired immunodeficiency syndrome as well as hepatitis and other blood-borne diseases are a threat to patients with bleeding disorders who need treatment with blood products, it is rewarding to realize that a number of these patients can be safely and effectively treated with their own desmopressin-stimulated F.VIII:C and vWF. Desmopressin is clinically useful for treatment of patients with moderate and mild hemophilia. The limits of the clinical indications are established by the nature of the bleeding episode, the resting factor level, the level that must be achieved, and the length of time the level must be maintained to manage any given bleeding episode. In von Willebrand disease, desmopressin can be used more extensively to raise F.VIII:C levels than in classic hemophilia, because fewer of the patients have the severe form of the disease that is unresponsive to desmopressin. Increases in the level of F.VIII:C of about four times the resting value can be expected both in hemophilia and von Willebrand disease, but it must be borne in mind that the range of individual responses is large. Even though it is not easy to correct the prolonged bleeding time, particularly in patients with dysfunctional vWF, this drawback is of clinical relevance only in a minority of cases. A role for the use of desmopressin in acquired diseases of primary hemostasis has been proposed more recently, and experience is more limited than in congenital bleeding disorders. Uremia is probably the most firmly established indication because it has been shown that the bleeding time is often dramatically shortened by desmopressin, and hemorrhages can be stopped or prevented before surgical procedures. The indications for use of the compound in liver cirrhosis and congenital and acquired platelet dysfunctions are promising but much less established from a clinical standpoint. The bulk of available clinical experience is based on intravenous administration. Intranasal and subcutaneous administration have been successfully attempted and might be more convenient in selected circumstances, such as home treatment and the stimulation of blood donors to provide more abundant supplies of F.VIII:C and vWF. However, the responses after intranasal administration are less predictable and consistent than after intravenous administration. Desmopressin has few troublesome side-effects. Mild facial flushing, a small increase in heart rate, and, more rarely, mild headache can occur transiently during infusion. Signs of hyponatremia or cerebral edema are extremely rare, providing that excessive fluid intake is avoided.(ABSTRACT TRUNCATED AT 400 WORDS)