The penis is hard when holding urine, which is a normal physiological phenomenon, because the venous return system of the penis is adjacent to the bladder, after holding urine, the bladder increases in a state of fullness, the full bladder will compress the venous return system of the penis, so that the venous return resistance of the penis increases, resulting in the symptoms of easy penile erection, so do not worry too much, timely emptying of urine, the penis will slowly return to the state of weakness. The actual fact is that you can find a lot of people who are not able to get a good deal on a lot of things. Severe long-term prostatitis can even cause the occurrence of sexual dysfunction diseases such as loss of libido, impotence and premature ejaculation.