Long-acting penicillin mainly refers to benzylpenicillin, there will be no so-called sequelae of taking benzylpenicillin, but there may be allergic and other adverse reactions to taking benzylpenicillin, these adverse reactions are not sequelae. Patients may have allergic reactions after taking benzylpenicillin, such as generalized long rash, leukopenia, interstitial nephritis, asthma attack, serum sickness type reaction, anaphylactic shock and so on. In addition, secondary infections may occur after prolonged use of benzylpenicillin, with secondary infections of Aureus, Gram-negative bacilli, or Candida that are resistant to benzylpenicillin. Benzathine penicillin is primarily used to prevent recurrence of rheumatic fever and is also used to treat streptococcal infections. It is important to note that patients with a previous allergy to any penicillin may be allergic to benzylpenicillin, and therefore the use of this drug is contraindicated in such patients. If you need to use benzylpenicillin, please do so under the supervision of a physician.