Floezy

Floezy Mechanism of Action

tamsulosin

Manufacturer:

Synthon Hispania

Distributor:

Maxxcare

Marketer:

Mega Lifesciences
Full Prescribing Info
Action
Pharmacotherapeutic group: α1A adrenoreceptor antagonist. ATC code: G04CA02.
Pharmacology: Mechanism of action: Tamsulosin binds selectively and competitively to the postsynaptic α1 adrenoceptors, in particular to subtypes αlA and αID. It brings about relaxation of prostatic and urethral smooth muscle.
Pharmacodynamics: Tamsulosin increases the maximum urinary flow rate. It relieves obstruction by relaxing smooth muscle in prostate and urethra thereby improving voiding symptoms.
It also improves the storage symptoms in which bladder instability plays an important role.
These effects on storage and voiding symptoms are maintained during long term therapy. Observational data indicate that use of tamsulosin may lead to a delay in the need for surgery or catheterization.
Alpha-blockers can reduce blood pressure by lowering peripheral resistance. No reduction in blood pressure of any clinical significance was observed during studies with tamsulosin in normotensive patients.
Pharmacokinetics: Absorption: The tamsulosin prolonged release formulation provides consistent slow release of tamsulosin, resulting in an adequate exposure, with little fluctuation over 24 hours.
Tamsulosin administered as tamsulosin prolonged release tablets is absorbed from the intestine. Of the administered dose, approximately 57% is estimated to be absorbed.
The rate and extent of absorption of tamsulosin administered as tamsulosin prolonged release tablets are not affected by food.
Tamsulosin shows linear pharmacokinetics.
After a single dose of tamsulosin in the fasted state, plasma concentrations of tamsulosin peak at a median time of 6 hours. In steady state, which is reached by day 4 of multiple dosing, plasma concentrations of tamsulosin peak at 4 to 6 hours, in the fasted and fed state. Peak plasma concentrations increase from approximately 6 ng/ml after the first dose to 11 ng/ml in steady state.
As a result of the prolonged release characteristics of tamsulosin prolonged release tablets the trough concentration of tamsulosin in plasma amounts to 40% of the peak plasma concentration under fasted and fed conditions.
There is a considerable inter-patient variation in plasma levels both after single and multiple dosing.
Distribution: In man, tamsulosin is about 99% bound to plasma proteins. The volume of distribution is small (about 0.2 l/kg).
Metabolism: Tamsulosin has a low first pass effect, being metabolized slowly. Most tamsulosin is present in plasma in the form of unchanged active substance. It is metabolised in the liver.
In rats, hardly any induction of microsomal liver enzymes was seen to be caused by tamsulosin.
No dose adjustment is warranted in hepatic insufficiency.
None of the metabolites is more active than the original compound.
Excretion: Tamsulosin and its metabolites are mainly excreted in the urine. The amount excreted as unchanged active substance is estimated to be about 4-6% of the dose, administered as Tamsulosin prolonged release tablets.
After a single dose of Tamsulosin prolonged release tablets and in steady state, elimination half-lives of about 19 and 15 hours, respectively, have been measured.
No dose adjustment is warranted in renal impairment.
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