Adult: Primary, secondary and latent: 1.8 g (2.4 MIU) as a single dose. Late (tertiary and neurosyphilis): 1.8 g (2.4 MIU) once wkly for 3 doses.
Intramuscular Streptococcal pharyngitis
Adult: 900 mg (1.2 MIU) as a single dose. Child: <27 kg: 225-450 mg (300,000-600,000 U) as a single dose; ≥27 kg: 675 mg (900,000 U) as a single dose.
Intramuscular Treponemal infections
Adult: 900 mg (1.2 MIU) as a single dose. Child: 450 mg (600,000 U) as a single dose.
Intramuscular Congenital syphilis
Child: Normal CSF: <2 yr 37.5 mg/kg (50,000 U/kg) as a single dose; 2-12 yr Adjust dosage based on adult dosage schedule.
Intramuscular Primary prophylaxis of rheumatic fever
Adult: 900 mg (1.2 MIU) as a single dose. Prevention of recurrence of acute attack: 900 mg (1.2 MIU) once every 3 or 4 wk or 450 mg (600,000 U) once every 2 wk. Child: <27 kg: 225-450 mg (300,000-600,000 U) as a single dose; ≥27 kg: 675 mg (900,000 U) as a single dose. Prevention of recurrence of acute attack: <27 kg: 450 mg (600,000 U) once every 3 or 4 wk; ≥27 kg: 900 mg (1.2 MIU) once every 3 or 4 wk.
Contraindications
Hypersensitivity to penicillins.
Special Precautions
Patient w/ previous hypersensitivity reactions to cephalosporins, history of allergy, asthma, seizure disorder. Not intended for IV or intra-arterial admin or inj near major peripheral nerves of blood vessels. Prolonged use may result in bacterial or fungal superinfection. Renal impairment.
Periodic evaluation of renal and haematopoietic functions. Assess culture and sensitivity test prior to initiation of therapy. Monitor for hypersensitivity reactions and opportunistic infections.
Drug Interactions
Bactericidal effect may be antagonised by tetracycline. Decreased rate of excretion and increased serum concentration when used w/ probenecid.
Lab Interference
May cause false-positive result in urinary and/or serum protein test, false positive or negative result for glycosuria test using copper sulfate reagent method, positive Coombs’ test.
Action
Description: Mechanism of Action: Benzathine benzylpenicillin interferes w/ bacterial cell wall synthesis during active multiplication causing cell wall death and resultant bactericidal activity against susceptible bacteria. Duration: 1-4 wk. Pharmacokinetics: Absorption: Slowly absorbed from the site of inj. Time to peak plasma concentration: W/in 12-24 hr. Distribution: Distributed throughout body tissues; CSF (minimal amount). Plasma protein binding: Approx 60%. Metabolism: Hydrolysed to benzylpenicillin. Excretion: Via urine.
J01CE08 - benzathine benzylpenicillin ; Belongs to the class of beta-lactamase sensitive penicillins. Used in the systemic treatment of infections.
References
Anon. Penicillin G Benzathine. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 05/09/2016.Bicillin L-A Injection (Pfizer Laboratories Div Pfizer Inc). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 05/09/2016.Buckingham R (ed). Benzathine Benzylpenicillin. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 05/09/2016.McEvoy GK, Snow EK, Miller J et al (eds). Penicillin G Benzathine. AHFS Drug Information (AHFS DI) [online]. American Society of Health-System Pharmacists (ASHP). https://www.medicinescomplete.com. Accessed 05/09/2016.Pfizer New Zealand Ltd. Bicillin L-A Injection data sheet 8 June 2012. Medsafe. http://www.medsafe.govt.nz/. Accessed 05/09/2016.