Penicillin G Benzathine

General

• Type: Penicillin, a type of Penicillin G
• Dosage Forms: IM
• Common Trade Names: Bicillin L-A

Adult Dosing

Streptococcal pharyngitis

• 1.2 million units IM x 1

Syphilis

• Primary, secondary, or latent <1yr
  • 2.4 million units IM x 1
• Latent >1yr or unknown duration, or tertiary
  • 2.4 million units IM qWeek x 3 weeks
• Neurosyphilis
  • 4 million units IV Q4H x10 days

Rheumatic Fever Prophylaxis, Secondary

• 1.2 million units IM every 4 weeks

Pediatric Dosing

Strep Pharyngitis

• <27kg: 0.6 million units IM x 1
• >27kg: 1.2 million units IM x 1

Syphilis

• Congenital (<1mo)
  • 50,000 units/kg IM x 1
  • Max: 2.4 million units/dose
  • Info: For asymptomatic disease only
• Acquired
  • Primary, secondary, or latent <1yr
    • 50,000 units/kg IM x 1
    • Max: 2.4 million units/dose
  • Latent >1yr or unknown duration
    • 50,000 units/kg IM qWeek x 3 weeks
    • Max: 2.4 million units/dose

Rheumatic Fever Prophylaxis, Secondary

• <27kg: 0.6 million units IM every 4 weeks
• >27kg: 1.2 million units IM every 4 weeks

Special Populations

• Pregnancy Rating: B
• Lactation: Safe
• Renal Dosing
  • Adult
    • CrCl 10-50: decrease dose 25%
    • CrCl <10: decrease dose 50-80%
    • Hemodialysis: give after dialysis without supplement
    • Peritoneal Dialysis: decrease dose 50-80%
  • Pediatric
    • CrCl 10-50: decrease dose 25%
    • CrCl <10: decrease dose 50-80%
    • Hemodialysis: give supplement
• Hepatic Dosing (Adult & Pediatric)
  • No data

Black Box

• Do not administer IV or mix with IV solutions (associated with cardiopulmonary arrest)

Contraindications

• Allergy to class/drug
• Anaphylactic reaction to Beta Lactams

Cautions

• Non-anaphylactic reaction to Beta Lactams
• Hypersensitivity to multiple compounds
• Asthma
• Recent antibiotic associated colitis
• Seizure disorder
• Renal imparement

Adverse Reactions

Serious

• Anaphylaxis
• Hypersensitivity reaction
• Exfoliative dermatitis
• Stevens Johnson Syndrome
• Superinfection
• Clostridium difficile
• Jarisch-Herxheimer reaction
• Hemolytic anemia
• Leukopenia
• Thrombocytopenia
• Nephrotoxicity
• Interstitial nephritis
• Seizures
• Neuropathy

Common

• Rash
• Urticaria
• Fever
• Puritis
• Fatigue
• Asthenia
• Headache
• Nausea and vomiting
• Diarrhea
• Injection site reaction
• Sterile abscess
• Elevated creatinine

Pharmacology

• Half-life: Unknown
• Metabolism: liver, CYP450
• Excretion: Urine
• Mechanism of Action: Bactericidal

See Also

• Penicillin G
• Antibiotics (Main)

References

Authors

Ross Donaldson