A double-blind study of prazosin in the treatment of Raynaud's phenomenon in scleroderma. Prazosin treatment of Raynaud's phenomenon: a double blind single crossover study. [Treatment of systemic scleroderma with ketanserin. Randomized, double-blind 6-months study of 27 cases]. Infusion of iloprost, a prostacyclin analogue, for treatment of Raynaud's phenomenon in systemic sclerosis. Efficacy and safety of Minipress XL, a new once-a-day formulation of prazosin. Double-blind studies of the clinical effectiveness of prazosin. Successful treatment of Raynaud's syndrome with Iloprost, a chemically stable prostacyclin analogue. Reduction of nightmares and other PTSD symptoms in combat veterans by prazosin: a placebo-controlled study. Controlled double-blind trial of dazoxiben and nifedipine in the treatment of Raynaud's phenomenon.
Nineteen patients with Raynaud's phenomenon in conjunction with progressive systemic sclerosis were given either prazosin hydrochloride (1 mg orally three times a day) or a placebo for eight weeks, after which the treatment procedure was reversed for four weeks. Prazosin was shown to be effective in reducing both the frequency and the severity of vasospasm reported by the patients. The efficacy of prazosin (Minipress) for the treatment of Raynaud's phenomenon (RP) was assessed by patient diary data and by objective measurements of digital vessel patency before and after cold challenge. Nine of the 14 patients with complete data reported fewer RP episodes during the 2 weeks in which they received prazosin than with placebo. Eight of 9 patients in Group 1 (systemic lupus erythematosus, mixed connective tissue disease or idiopathic RP) reported improvement during prazosin therapy (p less than 0.05) while only one of 5 patients with progressive systemic sclerosis (PSS, Group 2) reported benefit. Objective measurements indicated a significant decrease (p less than 0.02) in digital artery resistance with prazosin only in Group 1. These data predict that prazosin may be beneficial in the treatment of RP for patients who do not also have PSS. Twenty-seven patients with systemic scleroderma and Raynaud's phenomenon underwent a randomised double blind therapeutic trial: monotherapy with Ketanserine (80 mg/day for 6 months) against Placebo. The secondary effects were comparable in both groups as were the withdrawals from the trial for aggravation of Raynaud's phenomenon (one in each group). No significant difference was observed between the two groups as regards the evolution of the Raynaud's phenomenon or skin changes. Dysphagia was improved in the Ketanserine group (p less than 0.05) but not in the Placebo group. Some patients in the Ketanserine group experienced an improvement in the Raynaud's phenomenon at the end of the trial period; there were no improvements in the Placebo group. Three haemorrheological parameters (total blood viscosity, plasma viscosity and thixotropism) were abnormal at the beginning of the trial and did not improve by the end in the Ketanserine group. The K infinity coefficient of Quemada's law was normal at the start of the trial and increased after treatment (p less than 0.05). Iloprost, a stable prostacyclin analogue, was given by intravenous infusion to 29 patients with severe Raynaud's phenomenon, 26 of whom had systemic sclerosis (SS), and compared with placebo infusion in a double blind crossover trial. Iloprost significantly lessened the number and the severity of attacks compared with placebo. Nine patients expressed a preference for effectiveness of treatment, eight of these in favour of Iloprost. Thermography failed to show any long term effect of Iloprost. Side effects of headache, flushing, nausea, and vomiting were common, and the inconvenience of intravenous administration may limit its routine use. The efficacy and safety of prazosin GITS (gastro-intestinal therapeutic system), a new extended-release once-a-day formulation, were assessed both as monotherapy in mild essential hypertension and in combination with a diuretic in moderate essential hypertension in two multicenter, double-blind, placebo-controlled trials. Prazosin GITS (Minipress XL) given once daily in doses of either 10 or 20 mg significantly reduced sitting and standing systolic and diastolic blood pressure compared with placebo in both mild and moderate essential hypertension. There were minimal, clinically insignificant changes in heart rate following prazosin-GITS treatment (2.5, 10, and 20 mg) compared with placebo treatment. Prazosin GITS was well tolerated; the most common adverse experiences reported were headache, dizziness, and fatigue. All adverse experiences in the moderate hypertension group and the majority (91 percent) in the mild hypertension group were mild-to-moderate in severity. The results from these multicenter trials demonstrate the efficacy and safety of this new extended-release once-a-day formulation of prazosin in the treatment of patients with mild and moderate essential hypertension. In separate double-blind trials, prazosin was compared with placebo and with methyldopa and placebo. In both, prazosin was well tolerated and succeeded in lowering blood pressure in patients with mild to moderate hypertension. The mean reductions with methyldopa were greater, but the difference was not statistically significant and a higher percentage of the patients in the prazosin group became normotensive. Twelve female patients with severe secondary Raynaud's phenomenon were treated in a randomized order with both placebo and Iloprost infusions. Infusions were for 5 hours on 3 consecutive days and Iloprost was administered at variable dosage from 1.0 to 3.0 ng/kg/min. A 6-week follow-up period was used between the two sets of infusions. A significant number of patients reported Iloprost had improved Raynaud's symptomatology compared with placebo and this effect lasted for up to 6 weeks. The number of attacks of Raynaud's as recorded by patients in diary books was similarly reduced after Iloprost. Digital and nail-bed blood flows measured by laser-Doppler methods were increased for up to 6 weeks after Iloprost, but not after placebo infusions. Iloprost may be a useful therapeutic agent in the treatment of severe secondary Raynaud's syndrome. Prazosin is a centrally active alpha(1) adrenergic antagonist. The authors' goal was to evaluate prazosin efficacy for nightmares, sleep disturbance, and overall posttraumatic stress disorder (PTSD) in combat veterans.
                Ten Vietnam combat veterans with chronic PTSD and severe trauma-related nightmares each received prazosin and placebo in a 20-week double-blind crossover protocol.
                Prazosin (mean dose=9.5 mg/day at bedtime, SD=0.5) was superior to placebo for the three primary outcome measures: scores on the 1) recurrent distressing dreams item and the 2) difficulty falling/staying asleep item of the Clinician-Administered PTSD Scale and 3) change in overall PTSD severity and functional status according to the Clinical Global Impression of change. Total score and symptom cluster scores for reexperiencing, avoidance/numbing, and hyperarousal on the Clinician-Administered PTSD Scale also were significantly more improved in the prazosin condition, and prazosin was well tolerated.
                These data support the efficacy of prazosin for nightmares, sleep disturbance, and other PTSD symptoms. The prostaglandin thromboxane A2 causes platelet aggregation and vasoconstriction and may be important in the pathogenesis of Raynaud's phenomenon. Therefore, a randomized, double-blind, placebo-controlled trial was conducted to assess the effectiveness of dazoxiben, a selective thromboxane synthetase inhibitor, in the treatment of Raynaud's phenomenon and to compare it with nifedipine, a calcium channel blocker. Twenty-two subjects who had at least one episode of Raynaud's phenomenon per day entered the study. Three patients withdrew from the study because of side effects while taking nifedipine. There was no difference among the subjects' subjective evaluation of the three treatments. Seven of 19 (44 percent) reported a moderate to marked improvement while taking placebo compared with 12 of 19 (63 percent) taking nifedipine and five of 19 (26 percent) taking dazoxiben (p = NS). Similarly, there was no difference in the mean two-week episode rate among the three treatments: placebo 30.4 +/- 4.5, nifedipine 24.7 +/- 5.6, dazoxiben 32.0 +/- 4.9 (p = NS). Twelve of 22 subjects experienced side effects while taking nifedipine as compared with two of 21 taking placebo and eight of 21 taking dazoxiben (p less than 0.005). These data show that dazoxiben is not effective in the treatment of Raynaud's phenomenon and suggest that thromboxane does not cause the vasoconstriction that characterizes this disorder.
Prazosin is modestly effective in the treatment of Raynaud's phenomenon secondary to scleroderma.