Tadarise 10 MG Tablet is included in the PDE-5 inhibitor group of medicines because its main ingredient is Tadalafil. It inhibits the PDE-5 enzyme which is responsible for cGMP function in the body. Similarly, when the cGMP functions are affected, the muscles and blood vessels are relaxed and blood flows into the penis for getting erection. Remember that you can get a firm erection only when sexually stimulated. Men cannot get an erection without sexual stimulation no matter if they take ED pills. Also, it would be a side effect or overdose symptom if anyone suffers from prolonged erection without stimulus.