Tadapox is commonly marketed as a combination medicine containing tadalafil and dapoxetine. Tadalafil is a PDE5 inhibitor used for erectile dysfunction (ED), while dapoxetine is used for premature ejaculation (PE). The exact strengths can vary, so check the product packaging for the active ingredients and doses. Tadalafil improves blood flow to the penis during sexual stimulation, helping an erection develop and remain firm. Dapoxetine works through serotonin pathways and can help delay ejaculation. Neither ingredient is intended to increase sexual desire.