Flomax (Tamsulosin)

Chemical Name

(-)-( R) -5 – [2 - [[2 - (O-Etoksifenoksi) ethyl] amino] propyl]-2-metoksibenzolsulfonamid (as hydrochloride)
Gross formula

C20-H28-N2-O5-S
Characterization

White crystals. Poorly soluble in water and methanol, sparingly soluble in glacial acetic acid and ethanol, tamsulosin hcl practically insoluble in ether.
Pharmacological action

Mode of action – antidizuricheskoe, alpha-adrenoliticheskoe. Selectively blocks postsynaptic alfa_1A-adrenoreceptors of smooth muscles of the prostate, bladder neck and prostatic urethra. Ability to block alfa_1A-adrenoceptors 20 times, compared with the effect on alfa_1B-adrenoreceptors of smooth muscles of blood vessels (effects on systemic blood pressure slightly). Reduces the tone of smooth muscles of the prostate, bladder neck, prostatic urethra and improves urine flow and reduces symptoms obstruction and irritation of the urinary tract with benign prostatic hyperplasia zhelezy.Terapevtichesky effect develops in 2 ned.Posle Oral almost completely absorbed from the tamsulosin hcl 0.4 gastrointestinal tract (absorption 90%). Eating tamsulosin hcl 0.4 mg cap increases the bioavailability and the value C_max, reduces the time to reach C_max. C_max achieved after 4-5 h (when taking on an empty stomach) or 6-7 hours (at reception with food). The equilibrium concentration is set to 6-th day course intake, its peak value at 60-70% higher than C_max after a single oral administration. Binding to plasma proteins (mainly from alfa_1-glycoprotein) is 94-99%, is distributed over the volume of blood and extracellular fluid (volume of distribution – 0,2 l / kg). Slowly biotransformiruetsya in the liver, with the participation of cytochrome P450 with the formation of active metabolites (retain selectivity to alfa_1A-adrenoceptor), circulates in plasma mostly unchanged. T_1 / 2 – 9-13 h in healthy volunteers, 14-15 h – in patients tamsulosin hcl 0.4mg during treatment. Write mainly by the kidneys as metabolites conjugated with glucuronic and sulfuric acids (10% – unchanged), in part – with fekaliyami.Vvedenie tamsulosin male and female rats at doses of 43 mg / kg / day and 52 mg / kg / day, respectively, did not increase the incidence of tumors, with the exception of a moderate statistically significant increase in the incidence of mammary fibroadenoma in female rats at doses of 5.4 mg / kg.Otsenka the potential carcinogenicity in mice at doses 127 mg / kg / day (males) and 158 mg / kg / day (females) revealed no significant increase in the frequency of tumors in males, whereas females, within 2 years of receiving the highest dose of 45 mg / kg / day and 158 mg / kg / day was found a statistically significant increase in the incidence of fibroadenoma and adenocarcinoma of the breast. At the highest doses used to assess the carcinogenicity in mice, the values of AUC in animals at 8 times greater than those in humans at a dose of 0.8 mg / sut.Zaregistrirovannye cases of mammary tumors in female rodents are secondary and are due, apparently, tamsulosin-induced giperprolaktinemiey.Ne revealed mutagenic activity in several tests tamsulosin hcl in vitro and in vivo.V studies in male rats treated with tamsulosin once or repeatedly at a dose of 300 mg / kg / day (AUC value in rats at 50 times greater than, the observed humans at a dose of 0.8 mg / kg) found a significant reduction in fertility, possibly due to changes in the composition of seminal fluid or breach ejaculation. The effects were reversible, improvement was observed 3 days after tamsulosin hcl 0.4 receiving a single dose and 4 weeks after the end of repeated admission (full recovery was observed after 9 weeks). Repeatedly receiving doses of 10 and 100 mg / kg / day (up 1 / 5 and 16 of the estimated values of the AUC in humans), the negative impact on fertility is not nablyudalos.U female rats revealed a significant decrease in fertility rates for single or multiple injections R-isomer or racemic a mixture of tamsulosin at a dose of 300 mg / kg / day. Reduced fertility after a single dose, was apparently due to a violation of fertilization. When tamsulosin hcl 0.4mg multiple injections of a racemic mixture in a dose of 10 or 100 mg / kg / day of a negative effect on fertility in female rats was not detected.
Statement

Functional symptoms, including violation of urination, with benign prostatic hyperplasia.
Contraindications

Hypersensitivity, orthostatic hypotension in history, marked hepatic and / or renal failure.
Side effect

On the part of the nervous tamsulosin hcl 0.4 mg system and tamsulosin hcl sensory organs: 5-20% – dizziness, headache, asthenia, less than 5% – sleepiness / bessonnitsa.So the cardiovascular system and blood (hematopoiesis, hemostasis): less than 5% – orthostatic gipotenziya.So of the genitourinary system: retrograde ejaculation (8.4%) less than 5% – lowering libido.Prochie: 5-20% – back pain, rhinitis, tamsulosin hcl 0.4, diarrhea, and less than 5% – chest pain, nausea.
Drug Interactions

Simultaneous use with other alfa_1-blockers can lead to increased hypotensive effect. Cimetidine increases and tamsulosin hcl caps decreases furosemide concentrations in blood, diclofenac and warfarin increase the rate of excretion.
Overdose

Symptoms: possible acute gipotenziya.Lechenie: giving the patient lying position, the introduction plazmozameschayuschih solutions or vasoconstrictive drugs, to stop sucking – gastric lavage, activated charcoal or reception of osmotic laxative.
Precautionary measures

Before starting treatment you should verify the diagnosis (to exclude carcinoma of the prostate gland). Precautions apply at predisposition to orthostatic hypotension, disturbancies liver function and Cl creatinine below 10 ml / min. If signs of orthostatic hypotension (dizziness, weakness) the patient is recommended to seat or ulozhit.S use caution during the tamsulosin hcl 0.4 mg drivers of vehicles and people, trade is connected with increased concentration.
Dosing and Administration

Inside (after breakfast, drinking plenty of water) to 0.4 mg / day.