Therapeutic drugs for benign prostatic hyperplasia and hypertension
Benign prostatic hyperplasia (BPH) is a common disease in medium-elderly men. Prostatic hyperplasias obstruct urine excretion, which can cause irritant and obstructive urethral symptoms. The most common symptoms are nocturia, increased urgency during the day, frequent micturition, and urinary rheology. Many men over 70 years old have moderate or severe urethral symptoms due to BPH. Although BPH itself rarely endangers life, it can cause irreversible damage to the bladder or kidney if not treated. Acute urinary retention is the most serious complication of BPH. Its clinical features are sudden inability to urinate and pain. If not treated in time, it can endanger life. Alfuzosin is a selective alpha 1 receptor blocker, which belongs to the quinazoline derivative. By relaxing the tension of the urethra smooth muscle around the prostate, bladder neck and prostate, it can reduce the resistance of the urine flow, so that the symptoms such as urethral tension, resistance and pressure increase, bladder outlet obstruction and other symptoms related to prostatic hypertrophy can be alleviated. It has a quick effect and has little effect on the cardiovascular system, and there are no other adverse effects on sexual function like other annoying BPH drugs. The absorption of alfuzosin is good. The concentration of blood drug reaches peak 0.5-3 hours after taking, and the bioavailability is 64%. In the range of treatment dose, the pharmacokinetics is linear. About 87% of the drugs absorbed are combined with plasma protein. This product is mainly eliminated by liver metabolism.75%-91% of the inactive metabolite is excreted by the feces through the bile, and 15%-30% is excreted in the urine. Another 11% is excreted in the original form in the urine. The half-life of the elimination is 4-8 hours. Its pharmacokinetic characteristics are not affected by the meal.
In the elderly over 75 years of age, this product is absorbed faster and the concentration of the blood drug peak is higher. In addition, AUC is also higher than the young, but the volume of distribution can be reduced and the half-life will be eliminated. In renal insufficiency, it pharmacokinetic characteristics have no obvious change. In the patients with liver dysfunction, the concentration of blood drug peak, the elimination half life and the AUC value are all increased, and the free fraction is also increased. In addition, alfuzosin is similar to proposing and palavering in function. It not only blocks the alpha 1 receptor, but also smooths diastolic blood vessel muscle, so it has good antihypertensive effect. For high blood pressure, 7.5 to 10mg should be taken for 1 day 3 times daily.
It should be noticed that alfuzosin hydrochloride cannot be used with calcium antagonist and alpha blocker.
Alfuzosin hydrochloride is a post-synaptic a-antagonist useful in the symptomatic
treatment of benign prostatic hypertrophy and acute adenoma by lowering urethral
contractions induced by alpha, stimulation. Alfuzosin is also being developed as an
antihypertensive; its efficacy in this indication is comparable to prazosin with no
significant change in heart rate.
ChEBI: Alfuzosin is a monocarboxylic acid amide, a tetrahydrofuranol and a member of quinazolines. It has a role as an antineoplastic agent, an antihypertensive agent and an alpha-adrenergic antagonist.
Alfuzosin is also a quinazoline 1-blockerbut differs from terazosin in replacing the piperazine ring interazosin with an open piperazine ring (a rotatable propylenediaminegroup). Alfuzosin is more selective for thesubtype of α1A-receptor in the prostate gland than those invascular tissue. Thus, it has been used extensively in treatingBPH as a first-line drug with fewer cardiovascular sideeffects than terazosin and doxazosin.