Small red dots appearing on the legs and disappearing after a few days may be contact dermatitis, which usually does not require treatment; if they reappear or the symptoms are severe, medical attention is recommended.
If the contact substances contain allergic ingredients, such as shower gel, moisturizer, mosquito repellent, pants, etc., it may cause contact dermatitis, but because the contact time is short, or the scope of contact is small, so the symptoms are mild and can disappear on their own, and can be left untreated.
However, you should pay attention to the cause of allergy, try to avoid contact with allergic substances, if similar symptoms occur again, wash the contact area in a timely manner, stay away from contact with allergic substances, and if necessary, you can use anti-allergy drugs such as loratadine.
If the above symptoms occur, it is recommended to seek medical treatment as soon as possible, and use medication under the guidance of a doctor, do not self-medication.