The most well-known ED medications are Sildenafil and Tadalafil.
Both belong to a class of drugs known as phosphodiesterase type 5 (PDE5) inhibitors, and they work in a similar way.
These medications like generic cialis work best when sexual stimulation is present. When the PDE5 inhibitors are activated, a natural chemical is released, which the PDE5 inhibitors use to work.
A chain reaction begins when this natural chemical is released, relaxing the smooth muscle inside the penis.
The blood flow into the penis then increases, allowing the penis to become erect.