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 56,091 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This randomized, placebo-controlled, double-blind study was performed to evaluate the efficacy and safety of once-a-day terazosin (10 mg/day) in ambulatory patients (n = 57) with benign prostatic hyperplasia (BPH). After a 4-week placebo lead-in and a 24-week treatment period with terazosin (both single-blind), 30 patients who responded to terazosin were randomly assigned to either the terazosin or placebo treatment group for 12 weeks. During the single-blind treatment period, the peak urine flow rate increased 54% from a baseline average of 7.76 ml/sec to 11.92 ml/sec after terazosin; the mean flow rate increased 55% from a baseline of 4.90 ml/sec to 7.59 ml/sec; and the residual volume decreased 56% from 93.1 ml to 40.7 ml. The mean obstructive symptom score, irritative symptom score and physician's global assessment score improved by 68%, 34% and 27%, respectively. All these changes were significant (P less than 0.05) when compared to baseline values. During the double-blind period, the improvement in all the variables was sustained in the terazosin group but not in the placebo group. Peak and mean urinary flow rates, and physician's global assessment showed significant (P less than or equal to 0.05) differences at the end of the double-blind period. Adverse events occurred only during the single-blind period. The most frequent were headache (n = 6), asthenia (n = 3), and hypotension (n = 3). In summary, terazosin administered once-a-day improved the obstructive and irritative symptoms of BPH, urine flow rates and residual volume. Terazosin was well tolerated.
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PMID:Efficacy of once-a-day terazosin in benign prostatic hyperplasia: a randomized, double-blind placebo-controlled clinical trial. 168 73

Single intravenous doses of 1, 2, and 5 mg of terazosin and placebo were administered in a randomized, double-blind, crossover fashion to 12 hypertensive adult patients. Supine and sitting blood pressures and pulse rates were monitored before and for 48 hours after drug administration. Blood and urine specimens were obtained periodically up to 48 hours after dosing; the concentration of terazosin in these samples was then determined. When compared with values before dosing, significant reductions (p less than or equal to 0.05) in supine diastolic blood pressure were observed from as early as 10 minutes after infusion of a terazosin dose and including most measurements through nine hours. From 20 minutes to five hours, most of the mean decreases in supine diastolic blood pressure following infusion of terazosin were significantly greater than those following infusion of placebo. Mean changes after terazosin administration ranged from -3 to -14 mm Hg, whereas mean changes after placebo administration ranged from +2 to -7 mm Hg. Pulse rates tended to increase slightly after terazosin administration and decrease slightly after placebo administration with few changes achieving statistical significance. The onset of the antihypertensive effect (at least a 10 percent decrease in supine diastolic blood pressure) occurred within two hours after most terazosin doses. The magnitude of the antihypertensive effect was similar at all three doses. The duration of action continued for at least six hours in 40 percent of those patients who showed a response within two hours. The peak antihypertensive effect occurred approximately four hours after administration of the terazosin dose (mean decreases of 17, 18, and 19 mm Hg after the 1-, 2-, and 5-mg doses, respectively). Adverse effects were mild. The most frequently reported side effects were headache, nasal congestion, and light-headedness. Terazosin decayed in a biexponential fashion with an elimination half-life of about 12 hours. There was no indication that nonlinear elimination occurred or that hypertensive disease influenced the disposition of the drug.
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PMID:Efficacy and safety of intravenous terazosin in hypertensive patients. A preliminary report. 287 14

Terazosin is a post-synaptic alpha 1-adrenoceptor antagonist with a similar pharmacodynamic profile to prazosin. It differs from prazosin in having a longer duration of action, with an elimination half-life some 2 to 3 times that of prazosin, allowing the convenience of once daily administration. Moreover, its absorption from the gastrointestinal tract is more complete and predictable than that of prazosin which may facilitate dose titration. Terazosin therapy results in a significant reduction in blood pressure in patients with mild to moderate essential hypertension, with little influence on heart rate. The drug is an effective antihypertensive when administered as monotherapy or in combination with a range of antihypertensive agents including beta-blockers, diuretics and combinations of the two. In the few patients with congestive heart failure studied, terazosin produced an increase in cardiac output with a reduction in ventricular filling pressure and systemic vascular resistance, but no studies have been performed to assess the therapeutic potential of terazosin in this indication. Reductions in total plasma cholesterol and low density plus very low density lipoprotein cholesterol fractions have been reported after terazosin therapy, while high density lipoprotein cholesterol concentrations have tended to increase. Should such beneficial changes be confirmed in long term clinical studies they would suggest a therapeutic advantage of terazosin over some other antihypertensive drugs, particularly diuretics, which have been reported to adversely affect the plasma lipid profile. The most common side effects associated with terazosin treatment are dizziness, headache, asthenia and nasal congestion, but these are usually mild and do not require treatment discontinuation. Terazosin is normally administered once daily, starting at a dose of 1 mg/day and gradually titrating upwards as the blood pressure stabilises at each new dose, until blood pressure is adequately controlled or to a maximum dose of 20mg daily. First-dose syncope occurs rarely after terazosin, and can largely be avoided by giving the first dose at bedtime. Thus, terazosin offers a useful alternative to the drugs currently available for the management of mild to moderate essential hypertension either as monotherapy or in combination with other antihypertensive drugs.
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PMID:Terazosin. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic efficacy in essential hypertension. 288 69

The purpose of this study was to evaluate the effects of the alpha 1-blocking agent terazosin on blood pressure (BP) and blood lipids in a large, variant population of patients with hypertension. A total of 16,917 patients with hypertension were evaluated at 2214 primary and community care facilities; 7808 of these patients had not been treated previously for hypertension; 3928 were switched to terazosin from another antihypertensive agent; and 5181 received terazosin in addition to an agent that had not controlled their hypertension. Terazosin produced highly significant reductions in systolic (-18.2 +/- 0.2 mm Hg) and diastolic (-13.2 +/- 0.1 mm Hg) BP when used as monotherapy (mean dose, 3.1 mg; range, 2 to 10 mg) without causing a significant increase in heart rate. Equal antihypertensive efficacy was demonstrated in men, women, blacks, and whites of all ages, with particular benefit to elderly patients (> or = 65 years of age) with systolic hypertension. Comparative studies indicated that terazosin had equal antihypertensive efficacy in combination with diuretics, beta-blockers, calcium channel blockers, and angiotensin-converting enzyme (ACE) inhibitors. Patients who had not responded to monotherapy with one of these classes of antihypertensive drugs showed significant reductions of BP after terazosin, in the following average doses, was added to diuretics, 3.1 mg; beta-blockers, 3.4 mg; calcium channel blockers, 3.3 mg; and ACE inhibitors, 3.4 mg. Terazosin produced highly significant reductions in blood levels of total cholesterol (-5.0%), triglycerides (-6.1%), and low-density lipoprotein cholesterol (-7.6%) without change in high-density lipoprotein cholesterol when used as monotherapy. Similar favorable effects on blood lipid levels were demonstrated when terazosin was used in combination with all other classes of antihypertensive drugs. The greatest reductions in blood cholesterol (-9.2%) were observed among patients with hyperlipidemia (total cholesterol > or = 240 mg/dL). Terazosin maintained its antihypertensive efficacy and was well tolerated by patients with a variety of concomitant diseases, including congestive heart failure, peripheral vascular disease, chronic obstructive pulmonary disease, benign prostatic hyperplasia, diabetes, and obesity. Adverse effects occurred in 17.9% of patients and caused 2.2% to drop out of the study. The most frequent adverse effects were dizziness (4.8%), headache (2.5%), and asthenia (2.4%). Only 0.4% suffered syncope and 0.2% impotence. These data demonstrate the usefulness of terazosin as monotherapy or add-on therapy for treatment of hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Alpha 1-blockade for the treatment of hypertension: a megastudy of terazosin in 2214 clinical practice settings. 792 16

Benign prostatic hyperplasia (BPH) is a common disorder in elderly men which carries a substantial economic burden. Urinary symptoms associated with moderate to severe disease can significantly interfere with daily activities and reduce quality of life. Obstruction of urine flow in men with BPH can result from nonmalignant enlargement of the prostate gland (static component of BPH) and from alpha 1 receptor-mediated increased smooth muscle tone of the bladder neck and prostate (dynamic component of BPH). Transurethral resection of the prostate (TURP) is generally very effective and has traditionally been the standard treatment for men with moderate to severe BPH. However, response to therapy with TURP is not universal and the procedure is associated with a number of potential complications. Moreover, many men prefer to avoid or are not suitable candidates for this invasive procedure. Thus, there is an increasing role for less invasive treatment, including drug therapy, in men with moderate to severe BPH. Terazosin is an alpha 1 receptor antagonist which has been shown in placebo-controlled trials to significantly improve American Urology Association (AUA) symptom and quality-of-life scores and symptom problem index ('bother' score), as well as increase peak urinary flow rate, in men with BPH. In a recent large randomised US trial, treatment for 1 year with terazosin titrated to 10 mg/day improved mean AUA symptom score and peak urinary flow rate to a significantly greater extent than finasteride 5 mg/day in men with moderate to severe BPH. The most frequently reported adverse events associated with terazosin include dizziness, asthenia, postural hypotension, somnolence, headache, peripheral oedema, nasal congestion/rhinitis and syncope. Approximately 5% of men with BPH discontinue terazosin because of adverse events. Results of an economic evaluation of terazosin, in which both clinical and economic data were collected prospectively in a randomised placebo-controlled study design, showed similar total direct treatment costs per 1000 patients associated with 1 year of therapy with terazosin ($US3.57 million) and placebo ($US3.78 million) in men with moderate to severe BPH (1992 dollars). The analysis, which was conducted from the perspective of a managed care organisation in the US, demonstrated that the lower medication costs in the placebo group relative to the terazosin group were offset by increased inpatient care costs. Thus, terazosin (titrated to response up to a maximum of 10 mg/day) was significantly more effective than placebo in improving disease-specific symptoms and quality of life, but at a similar overall cost to placebo. Another economic analysis, also conducted from a third-party payer perspective in the US, modelled direct treatment costs associated with terazosin, finasteride and TURP during the first 2 years after initiating therapy in men with moderate to severe BPH. Results of the study favoured terazosin; the private insurance cost per patient undergoing primary treatment with TURP was $US6411, compared with $US2860 with finasteride (45% of the cost of TURP) and $US2422 with terazosin (38% of the cost of TURP). Medicare costs were lower for all 3 treatment groups but the relative comparisons were similar; corresponding costs per patient were $US3874, $US2161 and $US1820 (1992 dollars). A companion break-even cost analysis used a hypothetical cohort of men with BPH starting treatment at age 67 years. Private insurance costs associated with terazosin remained lower then those associated with TURP for approximately 15 years (the corresponding break-even point was 10 years for finasteride vs TRUP). Medicare costs associated with terazosin would not exceed those of TURP for approximately 7 years (5.5 years for finasteride vs TURP). In conclusion, a limited number of detailed pharmacoeconomic analysis of terazosin have been conducted to date, although it has not been compared with other a1 receptor antagonists.
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PMID:Terazosin. A pharmacoeconomic evaluation of its use in benign prostatic hyperplasia. 1016 27