Formulation of double-layer Tadalafil and Amlodipine complex tablets to treat erectile dysfunction and hypertension

Many men over the age of 40 suffer from erectile dysfunction (ED) for a variety of reasons. In addition, more than 40% of ED patients have hypertensive disease at the same time. Tadalafil (TD) is a selective and reversible inhibitor of cyclic guanosine monophosphate-specific phosphodiesterase type 5 (cGMP-specific PDE-5). It is an insoluble drug with biopharmaceutics classification system class-II and was prepared by wet granulation with a solubilizing agent. Amlodipine besylate (AM) is a calcium channel antagonist that is effective in preventing systolic hypertension and stroke, and is manufactured using physical mix method. We used TD and AM to fabricate a double-layer complex tablet that can prevent or treat two diseases at the same time. Scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), X-ray diffraction (XRD) were analyzed for confirming chemical and physical characterization. Also, in vitro dissolution test was conducted to evaluate the dissolution rate of tablet at pH=1.2. In conclusion, the rapid release of two drugs in the double layer tablet was confirmed and could be applied as a pharmaceutical therapeutic agent.