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    Prescription under medical supervision


    Therapeutic action

    • Long-acting penicillin antibacterial


    • Early syphilis (primary, secondary, or early latent infection of less than 12 months duration)
    • Late latent syphilis (infection of more than 12 months duration or of unknown duration)
    • Congenital syphilis (absence of clinical signs in the neonate and adequate treatment in the mother)
    • Endemic treponematoses (yaws, bejel, pinta)
    • Streptococcal tonsillitis 
    • Prophylaxis of diphtheria in the event of direct contact
    • Primary and secondary prophylaxis of rheumatic fever

    Forms and strengths, route of administration

    • Powder for injection in vials of:
      • 1.2 MIU (900 mg), to be dissolved in 4 ml of water for injection, for IM injection
      • 2.4 MIU (1.8 g), to be dissolved in 8 ml of water for injection, for IM injection



    • Child: 50 000 IU (37.5 mg)/kg per injection (max. 2.4 MIU or 1.8 g per injection)
    • Adult: 2.4 MIU (1.8 g) per injection


    Yaws, bejel, pinta

    • Child under 10 years: 1.2 MIU (900 mg) per injection
    • Child 10 years and over and adult: 2.4 MIU (1.8 g) per injection


    Streptococcal tonsillitis, prophylaxis of diphtheria, prophylaxis of rheumatic fever

    • Child under 30 kg: 600 000 IU (450 mg) per injection
    • Child 30 kg and over and adult: 1.2 MIU (900 mg) per injection


    • Early syphilis, congenital syphilis, tonsillitis, yaws, bejel, pinta, prophylaxis of diphtheria, primary prophylaxis of rheumatic fever: single dose
    • Late latent syphilis: one injection/week for 3 weeks
    • Secondary prophylaxis of rheumatic fever: one injection every 4 weeks for several years

    Contra-indications, adverse effects, precautions

    • Do not administer to penicillin-allergic patients.
    • Administer with caution to patients allergic to cephalosporins (cross-sensitivity may occur) and renal impairment (reduce dosage).
    • May cause:
      • gastroinstestinal disturbances, pain at injection site, allergic reactions sometimes severe;
      • Jarisch-Herxheimer reaction (fever, chills, myalgia, tachycardia) in patients with syphilis;
      • convulsions in the event of high dosages or renal impairment;
      • symptoms of shock with neuropsychiatric disorders in case of accidental IV injection.
    • Ensure that the IM injection does not enter a blood vessel.
    • Do not combine with methotrexate.
    • Pregnancy and breast-feeding: no contra-indication


    • For a 2.4 MIU (1.8 g) dose, administer 1.2 MIU (900 mg) in each buttock.
    • Do not confuse long-acting benzathine benzylpenicillin, for IM injection, with rapidly acting benzylpenicillin (or penicillin G), administered by Iv route.
    • Do not mix with other drugs in the same syringe.


    –  Below 25 °C 
    Once reconstituted, suspension must be used immediately.