The rupture of the side of the foreskin of a boy may be caused by trauma to the foreskin or glans phimosis. You can go to the hospital in time for suture or use antibacterial drugs to apply and keep the surrounding clean. 1. During sex or masturbation, if a man exerts too much force, it can lead to strong stimulation of the side of the foreskin, and thus rupture occurs. They should go to the hospital in time for suture to avoid the wound being too big, which may lead to wound infection in serious cases. Avoid excessive force during sex and frequent masturbation. 2. If the circumcision is due to inflammation of the surrounding tissues, resulting in congestion and edema, the wound may ulcerate and lead to rupture of the side of the foreskin. You can use local antibacterial drugs such as erythromycin under the guidance of a doctor. Pay attention to the cleanliness of the foreskin to avoid aggravating the infection. Please pay attention to the side effects and adverse reactions of the drugs, please use the above drugs under the guidance of the doctor. The side of the foreskin rupture should seek medical treatment as soon as possible to avoid causing delays.