1, probably because of skin allergy or infection with the sarcophagus, resulting in itchy skin when sleeping, unconsciously scratching the wall with hands or feet, thus leaving scratches.
2, it may also be because the skin lacks water or suffers from urticaria, causing skin scratches, that is, artificial urticaria. In this case, it is very sensitive and may be uncontrollable.
If it is skin itching caused by skin allergy, it is recommended to go to dermatology for professional treatment in time to avoid secondary infection or complications. If the skin is slightly itchy due to dryness or lack of water, you can pay attention to keeping the skin clean and moist, use mild toiletries and skin care products, and avoid irritating items such as rough towels or inferior soap.