Fildena Chewable 100 Mg contains sildenafil citrate, a potent inhibitor of phosphodiesterase type 5 (PDE5). By inhibiting PDE5, sildenafil enhances the effects of nitric oxide, leading to smooth muscle relaxation in the penile arteries and corpus cavernosum, thereby promoting blood flow and facilitating erections. Additionally, sildenafil may also exert effects on the smooth muscle cells in the prostate gland, potentially contributing to the management of BPH symptoms.