This article is from "Nankai Sun Pharmacist", which is used for medical science popularization for reference. Finasteride is a competitive inhibitor of 5-reductase, which can inhibit the activity of 5-reductase, so that testosterone cannot be converted into dihydrotestosterone, thereby preventing prostatic hyperplasia, reducing the volume of the prostate, increasing the maximum urinary flow rate, improving clinical symptoms such as dysuria, and reducing the risk of acute urinary retention and prostatectomy. Both doxazosin and tamsulosin are highly selective ɑ1 receptor blockers, which can selectively antagonize ɑ1 receptors on the smooth muscle of the urinary tract, and significantly improve symptoms such as dysuria, frequent urination at night, and residual urine sensation caused by prostatic hyperplasia. Doxazosin ordinary tablets can cause blood pressure to decrease, controlled-release tablets have little effect on blood pressure, tamsulosin has no obvious effect on blood pressure, no first dose effect, and the first dose does not need to be reduced or emphasized before bedtime.
Finasteride 5 mg once a day, patients with renal insufficiency do not need to adjust the dose, and in patients over 70 years of age, finasteride clearance is reduced, but does not need to adjust the dose. Due to the slow onset of action of finasteride and the satisfactory effect will be exerted after 3 months of medication, the current clinical strategy is to use finasteride in combination with ɑ receptor antagonists such as doxazosin or tamsulosin when starting prostatic hyperplasia drugs, so as to rapidly improve the symptoms of poor urination. Patients with hepatic insufficiency should use with caution.
When taking doxazosin controlled-release tablets, the drug should be swallowed completely with a sufficient amount of liquid, and should not be chewed, broken or crushed before taking, and its efficacy is not affected by whether it is eaten or not. The most common dose is 4 mg once a day. The maximum initial dose for clinical use abroad is 8mg, once a day, and there is no more relevant clinical experience in China. Commonly used doses of doxazosin can be used in patients with renal insufficiency and elderly patients, and patients with hepatic insufficiency should be used with caution. The first dose of doxazosin can cause the first dose of syncope or sudden loss of consciousness, so the first ** should be started at night before bedtime. In controlled-release tablets, doxazosin is placed in a nonabsorbable shell and released slowly, and the drug is expelled in an empty shell that can be seen in the stool.
Tamlo new once 02 mg once a day after meals, the dose can be increased or decreased according to age and symptoms. Sustained-release tablets should be swallowed whole, should not be chewed, broken or crushed before consumption, sustained-release capsules can be opened for consumption, but do not chew the particles inside the capsule, so as not to lose the sustained-release effect. When changing from a sitting or lying position after taking the drug, the movement should be slow, long-term users should avoid sudden arrest, and closely monitor blood pressure changes during medication, especially those who are combined with antihypertensive drugs. People who are allergic to sulfonamides may have an increased risk of allergic reactions to tamsulos.
Adverse effects of finasteride are mainly affected sexual function (decreased libido, erectile dysfunction, ** disorder) and breast discomfort (breast hyperplasia, breast swelling, tenderness), and there may be a rash. The above adverse reactions decreased year by year with the extension of ** time. Other adverse reactions reported after marketing include itching, rubella, allergic reactions such as swelling of the face and lips, and **pain.
The most common adverse effects of doxazosin are orthostatic hypotension (rarely with syncope) or nonspecific symptoms, including: dizziness, headache, fatigue, malaise, peripheral edema, weakness, drowsiness, gastrointestinal reactions (nausea, vomiting, abdominal pain, diarrhoea, gastroenteritis), dry mouth, back pain, chest pain, palpitations, tachycardia, cough, itching, urinary incontinence, cystitis, and rhinitis.
The following adverse events have been reported after the marketing of doxazosin tablets: tremor and irritability (rare cases), and occasional sexual dysfunction has been reported. Allergic reactions to drugs such as rash, thrombocytopenia, purpura, epistaxis, leukopenia, hematuria, cholestasis, jaundice, abnormal liver function tests, hepatitis, and blurred vision have also been reported. Other serious adverse reactions: flaccid iris syndrome.
Tamsulosin is common with headache, dizziness, insomnia, drowsiness, fatigue, waddling, back pain and other adverse reactions. Occasionally, orthostatic hypotension, increased heart rate, nausea, vomiting, stomach upset, lack of appetite, elevated aminotransferases, nasal congestion, edema, dysphagia, abnormality, rash, etc., if a rash is found, the drug should be discontinued. Serious adverse reactions include persistent erection (rare) and retinal detachment.