Recommended starting doses of tadalafil are 10 mg for on-demand dosing and 2.5 mg for once-daily dosing, and these doses can then be titrated up or down according to the efficacy and tolerability. It is absorbed as a low-solubility and high-permeability, or Class 2, drug within the FDA Biopharmaceuticals Classification System. With oral ingestion, after [...]

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Tadalafil is at least 9000 times more selective for PDE5 than most of the other families of PDEs, with the exception of PDE11. PDE11 is found in the testes and prostate; however, despite partial inhibition of PDE11 by tadalafil at therapeutic doses, clinical significance of this observation has yet to be fully understood. A study [...]

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