What is Fildena 100? Fildena 100 is a generic Viagra medication used in the treatment of erectile dysfunction or impotence. The main active ingredient in Fildena is Sildenafil Citrate, which is the same ingredient found in Viagra. Fildena 100 is manufactured by Fortune Healthcare, a well-known pharmaceutical company based in India. The company has been in business for over 10 years and is GMP certified by the WHO. How does Fildena 100 work? Fildena 100 works by inhibiting the enzyme PDE5, which is responsible for the breakdown of cGMP. When cGMP is broken down, blood flow to the penis is reduced, causing erectile dysfunction. Fildena 100 prevents the breakdown of cGMP, allowing more blood to flow to the penis and resulting in an erection. What are the side effects of Fildena 100? The most common side effects of Fildena are headache, flushing, and upset stomach. These side effects are typically mild and resolve on their own. More serious side effects of Fildena 100 are rare but can include priapism (a painful erection lasting more than 4 hours), vision changes, and hearing loss. If you experience any of these side effects, you should seek medical help immediately.