Tamsulosin is a urinary-selective α-1 antagonist.
Alpha-1-adrenoceptors are highly concentrated in the urethral smooth muscles, where their tone is maintained by stimulation of postjunctional a1-adrenoceptors through the release of noradrenaline from the adrenergic nerves.
Recommended dose in dogs is 30 - 100 μg/kg given two to three times daily.
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