Drug information of benzathine penicillin

Mechanism of effect

Interferes with cell wall mucopeptide synthesis during active multiplication, resulting in bactericidal activity against susceptible microorganisms

Pharmacodynamic

The bactericidal activity of penicillin G results from the inhibition of cell wall synthesis and is mediated through penicillin G binding to penicillin binding proteins (PBPs).

Pharmacokinetics

Half-Life: 20-30 minutes after hydrolysis to penicillin G

Absorption: IM, slow

Peak Plasma Concentration: 0.03-0.05 units/mL; levels persist for 5-14 days depending on dose

Protein Bound: 60%

Metabolism: ~30% in liver

Excretion: urine (60-90%)

Drug indications

pneumonia , Skin or Soft Tissue Infection

Dosage

• Adult

Note: Bicillin C-R 900/300 is only indicated in pediatric patients.

Pneumococcal infections (except meningitis): IM: 1.2 million units on day 1; may be repeated every 2 or 3 days until afebrile for 48 hours.

Streptococcal infections, group A: IM: 2.4 million units in a single dose. Note: Alternatively, 50% of the total dose can be administered on day 1 and 50% on day 3. For treatment of group A streptococcal pharyngitis in adults, penicillin G benzathine (Bicillin L-A) is preferred

·         Pediatric

Pneumococcal infections (except meningitis): Infants and Children: IM:

Bicillin C-R: 600,000 units on day 1; may repeat every 2 to 3 days until afebrile for 48 hours

Bicillin C-R 900/300: 1.2 million units on day 1; may repeat every 2 or 3 days until afebrile for 48 hours

Streptococcal infections, group A:

Infants, Children: IM:

Bicillin C-R:

<14 kg: 600,000 units in a single dose

14 to 27 kg: 900,000 units to 1.2 million units in a single dose

Bicillin C-R 900/300: 1.2 million units in a single dose

Children and Adolescents (>27 kg): IM:

Bicillin C-R 900/300: 1.2 million units in a single dose

Note (Bicillin C-R only): Alternatively, 50% of the total dose can be administered on day 1 and 50% on day 3.

Rheumatic fever, primary prevention (Bicillin C-R 900/300) (off-label use): Infants and Children 6 months to 12 years and Adolescents ≤14 years: IM: 1.2 million units as a single dose

Side effects

Pain , Fever , Headache , nausea , dizziness , vomiting , Blurred vision , vertigo , palpitations , itching , hallucinations , general discomfort , swelling , Restlessness , redness or flaking of treated skin

Interactions

cholera vaccine live , Omadacycline

Alerts

• Not for IV use
• Do not inject IV or admix with other IV solutions
• Reports of inadvertent IV administration associated with cardiorespiratory arrest and death
• Prior to administration, carefully read the warnings, adverse reactions, and dosage and administration sections of the labeling
• For deep IM administration only; do not administer IV, SC, or IT
• Do not inject near nerve or artery
• Pseudomembranous colitis reported with antibacterial agents, including penicillin G

Points of recommendation

• Benzathine penicillin and procaine penicillin is injected into a muscle.
• Benzathine penicillin and procaine penicillin must be injected slowly into a muscle of the buttock or upper thigh.
• Do not inject the medication into a vein or life-threatening side effects could result.
• Benzathine penicillin and procaine penicillin is sometimes given only once or only for a few days until your symptoms clear up. Be sure to have all injections your doctor has prescribed. Your symptoms may get better before the infection is completely cleared.
• Use this medication for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Benzathine penicillin and procaine penicillin will not treat a viral infection such as the common cold or flu.

Pregnancy level

B