Oral penicillin requires a skin test. Penicillin, an antibiotic used to treat infections caused by sensitive bacteria, is widely used in clinical practice, but there is also a relatively high incidence of allergic reactions resulting from its use. Since penicillin allergic reactions are mostly type I anaphylactic reactions that occur only in specific groups of people, the occurrence of penicillin allergic reactions is not related to the dose of the drug. People who are highly allergic to penicillin can go into shock even at very small doses. The role of the penicillin skin test is primarily to prevent the occurrence of allergic reactions, especially severe ones. Therefore, whether penicillin is administered by mouth or by injection or by other means, a skin test is required, and penicillin may only be administered if the skin test is negative. It is important to note that the skin test should be performed in a regular hospital with resuscitation equipment so that timely resuscitation can be provided in case of an allergic reaction. In case of discomfort during the use of penicillin, medical personnel should be informed promptly and the use of penicillin should be discontinued.