You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Which of the following alpha-blocker drug is used in the treatment of benign hypertrophy of prostate without producing significant hypotension? and explain in detail?
Ans. d (Tamsulosin). (Ref. KD Tripathi 6th/pg. 135)DRUG USED FOR BHP# Alpha-adrenergic blockers:- Terazosin,- Tamsulosin,- Doxazosin:# A 5-a reductase inhibitor - finasteride- Finasteride prevents conversion of testosterone to dihydrotestosterone.# Cyproterone acetate (Anti-androgenic drug) is used for medical castration.Terazosin# It is reversible al-selective antagonist that is effective in hypertension;# It has also been approved for use in men with urinary symptoms due to BPH.# Terazosin has high bioavailability# But is extensively metabolized in liver (only a small unchanged fraction excreted in urine)# The half-life of terazosin is 9-12 hours.Doxazosin# Is efficacious in the treatment of hypertension and BPH.# It differs from prazosin and terazosin in having a longer half-life of about 22 hours.# It has moderate bioavailability and is extensively metabolized, with very little parent drug excreted in urine or feces.# Doxazosin has active metabolites, although contribution to the drug's effects is probably small.Tamsulosin# It is an uroselective a1A/1D antagonist with a structure quite different from that of most other al-receptor blockers.Q# It has high bioavailability and a long half-life of 9-15 hours.# It is metabolized extensively in the liver.# Tamsulosin has higher affinity for alA and alD receptors than for the alB subtype.# The drug's efficacy in BPH suggests that the alA subtype may be the most important subtype mediating prostate smooth muscle contraction.# Furthermore, compared with other antagonists, tamsulosin has less effect on standing blood pressure in patients (causes minimal vascular side effects).# Dizziness and retrograde ejaculation are the only vital side-effects.Alfuzosin# is an al-selective quinazoline derivative that has also been shown to be efficacious in BPH. It has bioavailability of 60%, is extensively metabolized, and has elimination halflife of about 5 hours.Indoramin# It is another al-selective antagonist that also has efficacy as an antihypertensive.Urapidil# It is an al antagonist (its primary effect) that also has weak 2-agonist and 5-HTlA-agonist actions and weak antagonist action at al receptors.# It is used in Europe as an antihypertensive agent and for benign prostatic hyperplasia.