Category:

• Antibiotic

Description:

• Penicillin, Natural

Indications:

• Refer to Penicillin G Aqueous monograph

Contraindications:

• Never use IV

Precautions:

• Pregnancy category B

• Use with caution in patients with penicillin or cephalosporin allergy (5-10% chance of cross-reactivity)

• Deep intramuscular injection only into the upper, outer quadrant of the buttocks

Adverse Reactions (Side Effects):

• Hypersensitivity

• Gastrointestinal: nausea, vomiting, diarrhea

• Vaginitis  

Dosage:

Administered by IM injection ONLY

• Pneumococcal infections:

  • Adult: 600,000 to 1 million units per day

  • Children (<60kg): 300,000 units per day

• Streptococcal infections (Group A):

  • Adult: 600,000 to 1 million units per day

  • Children (<60kg): 300,000 units per day

• Bacterial endocarditis:

  • Adult: 600,000 to 1 million units per day

• Staphylococcal infections:

  • Adult: 600,000 to 1 million units per day

  • Children (<60kg): 300,000 units per day

• Rat-bite fever

  • Adult: 600,000 to 1 million units per day

• Erysipeloid endocarditis

  • Adult: 600,000 to 1 million units per day

• Diphtheria

  • Adjunct to antitoxin: 300,000-600,000 units per day

  • Carrier state: 300,000 units per day for 10 days

• Anthrax (cutaneous):

  • 600,000 to 1 million units per day for 10 days

• Syphilis:

  • Primary, secondary and latent: 600,000 units per day for 8 days

  • Late (tertiary, neurosyphilis): 600,000 units per day for 10-15 days

  • Neurosyphilis: 2.4 million units per day (with probenecid 500mg orally qid) for 10-14 days

  • Congenital: 50,000 units/kg/day (one IM dose) for 10 days

• Yaws (bejel and pinta): 

  • treat same as syphilis in corresponding stage of disease

• Gonorrheal infections:

  • 4.8 million units divided into at least two doses at one visit with 1 gram of probenecid between doses

• Vincent’s gingivitis and pharyngitis:

  • 600,000 to 1 million units per day