How long it takes for the stomach pain of allergic purpura to go away needs to be determined by whether the medication is applied in time and the severity of the stomach pain. If the stomach pain is very severe and there are tarry stools, you need to immediately administer pantoprazole injection or omeprazole injection, which usually can be relieved in 3-5 days and can subside in more than 7-10 days. If there is only mild stomach pain, oral lansoprazole tablets or omeprazole tablets can be taken, which can usually subside or be relieved in 3-7 days. It is also necessary to actively cooperate with compound glycyrrhizic acid monoammonium S sodium chloride injection in order to be able to treat the primary disease in a timely manner, which can shorten the average treatment time by 2-3 days if such treatment is effective.