Penicillin G aqueous

Penicillin G aqueous is a prescription medication used for the treatment of: 

• Meningococcal meningitis/septicemia
• Actinomycosis
• Botulism
• Vincent’s infection
• Rat-bite fever
• Listeria infections
• Pasteurella infections
• Erysipeloid
• Diphtheria
• Anthrax
• Syphilis
• Streptococcal Group B infection
• Endocarditis
• Neonatal bacterial infection

Penicillin G aqueous is available under the following different brand names: Pfizerpen, penicillin G potassium, penicillin G sodium, Crystapen

Adult and pediatric dosage

Premixed injectable solution

• 1 million units/50mL
• 2 million units/50mL
• 3 million units/50mL

Potassium, powder for injectable solution

• 5 million units/vial
• 20 million units/vial

Sodium, powder for injectable solution

• 5 million units/vial

Meningococcal Meningitis/Septicemia

Adult dosage

• 20-30 million units/day IV continuous infusion x14 days or afebrile x7days, OR
• 200,000-300,000 units/kg/day IV divided every 2-4hours x24 doses

Actinomycosis

Adult dosage

• Cervicofacial cases: 1-6 million units/day IV
• Thoracic and abdominal disease: 10-20 million units/day IV divided every 4-6hrs x for 6 weeks, may follow with penicillin V

Botulism

Adult dosage

• Adjunctive to antitoxin: 20 million units/day IV divided every 4-6hrs

Vincent’s Infection (fusospirochetosis)

Adult dosage

• 5-10 million units/day IV divided every 4-6hrs

Rat-Bite Fever

Adult dosage

• 12-20 million units/day IV divided every 4-6hrs for 3-4 weeks

Listeria Infections

Adult dosage

• Meningitis: 15-20 million units/day IV divided every 4-6hrs for 2 weeks
• Endocarditis: 15-20 million units/day IV divided every 4-6hrs for 4 weeks

Pasteurella Infections

Adult dosage

• Bacteremia or meningitis: 4-6 million units/day IV divided every 4-6hr for 2 weeks

Erysipeloid

• Endocarditis

Adult dosage

• 12-20 million units/day IV divided every 4-6hrs for 4-6 weeks

Pediatric dosage

• Infants and Children weighing less than 45 kg: 250,000 units/kg/day IV divided every 4hrs

Diphtheria

• Adult dosage
• Adjunct to antitoxin or to prevent carrier state: 2-3 million units/day IV divided every 4-6hrs for 10-12 days

Anthrax

Adult dosage

• Minimum: 5 million units/day IV
• 12-20 million units/day IV have been used

Streptococcal Infections

Adult dosage

• Empyema, pneumonia, pericarditis, endocarditis, meningitis: 5-24 million units/day IV divided every 4-6hrs

Syphilis

Adult dosage

• Neurosyphilis: 18-24 million units/day IV for 10-14 days

Pediatric dosage

• Neonates less than 7 days: 100,000 units/kg/day IV divided every 12hrs
• Neonates less than 7 days: 150,000 units/kg/day IV divided every 8hrs

Streptococcal Group B Infection

Adult dosage

• Prophylaxis: 5 million units IV at the onset of labor or after membrane rupture followed by 2.5 million units IV every 4hrs until delivery

Neonatal Bacterial Infection General Dosing Guidelines

Pediatric dosage

• Below 7 days & weighing less than 2000 g: 50,000 units/kg/day IV divided every 12hr  
• Below 7 days & weighing more than 2000 g: 75,000 units/kg/day IV divided every 8hr
• Above 7 days & weighing less than1200 g: 50,000 units/kg/day IV divided every 12hr
• Above 7 days & weighing 1200-2000 g: 75,000 units/kg/day IV divided every 8hr
• Above 7 days & weighing more than 2000 g: 100,000 units/kg/day IV divided every 6hrs

Infant & Children Bacterial Infection General Dosing Guidelines

Pediatric dosage

• Moderate Infection: 25,000-50,000 units/kg/day IV/IM divided every 6hrs 
• Severe Infection: 250,000-400,000 units/kg/day IV/IM divided every 4-6hrs
• Not to exceed 24 million units/day

Meningitis

Pediatric dosage

• Neonates less than 7 days & weighing less than 2000 g: 100,000 units/kg/day IV divided every 12hrs
• Neonates less than 7 days & weighing more than 2000 g: 150,000 units/kg/day IV divided every 8hrs
• Neonates above 7 days & weighing less than 1200 g: 100,000 units/kg/day IV divided every 12hrs
• Neonates above 7 days & weighing 1200-2000 g: 150,000 units/kg/day IV divided every 8hrs
• Neonates above 7 days & weighing more than 2000 g: 200,000 units/kg/day IV divided every 6hrs
• Infants & Children: 250,000-400,000 units/kg/day IV divided every 4hrs; not to exceed 24 million units/day

Group B Streptococcal Meningitis

Pediatric dosage

• Neonates less than 7 days: 250,000-450,000 units/kg/day IV divided every 8hrs 
• Neonates more than 7 days: 450,000 units/kg/day IV divided every 6hrs

Dosage Considerations – Should be Given as Follows: 

• See “Dosages”

Common side effects of Penicillin G aqueous include:

• injection site irritations (pain, redness, swelling, bruising, or irritation),
• twitching or muscle spasms,
• overactive reflexes,
• mild skin rash,
• nausea,
• vomiting,
• upset stomach,
• diarrhea,
• black or hairy tongue,
• fever,
• chills,
• muscle pain,
• headache,
• fast heart rate,
• hyperventilation,
• flushing,
• low blood pressure,
• itching,
• rash,
• swelling of the face, throat, tongue, and lips, and
• difficulty breathing

Serious side effects of Penicillin G aqueous include:

• hives,
• itching,
• swelling under the skin (edema),
• fast heart rate,
• swelling of the vocal cords,
• difficulty breathing,
• low blood pressure
• vascular collapse,
• diarrhea,
• fever,
• weakness,
• joint pain,
• abdominal pain, and
• rash

Rare side effects of Penicillin G aqueous include:

• none 

This is not a complete list of side effects and other serious side effects or health problems may occur as a result of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first

• Penicillin G aqueous has severe interactions with no other drugs.
• Penicillin G aqueous has serious interactions with at least 10 drugs
• Penicillin G aqueous has moderate interactions with at least 21 other drugs
• Penicillin G aqueous has minor interaction with at least 12 drugs. 

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you and share this information with your doctor and pharmacist. Check with your health care professional or doctor for additional medical advice, or if you have health questions, concerns.

Contraindications

• Allergy to penicillins, cephalosporins, imipenem

Effects of drug abuse

• None

Short-Term Effects

• See “What Are Side Effects Associated with Using Penicillin G aqueous?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Penicillin G aqueous?”

Cautions

• Serious and occasionally fatal hypersensitivity (anaphylactic) reactions reported; reactions likely to occur in individuals with a history of penicillin hypersensitivity and/or a history of sensitivity to multiple allergens; before initiating therapy, inquire about previous hypersensitivity reactions to penicillins, cephalosporins, or other allergens; discontinue and institute appropriate therapy If an allergic reaction occurs
• Severe cutaneous adverse reactions (SCAR), such as Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP) reported when SCAR is suspected, discontinue therapy and consider an alternative treatment
• The use of antibiotics may promote overgrowth of nonsusceptible organisms, including fungi; indwelling intravenous catheters encourage superinfections; should superinfection occur, appropriate measures should be taken; when indicated, incision and drainage or other surgical procedures should be performed in conjunction with antibiotic therapy
• Care should be taken to avoid intravenous or accidental intraarterial administration, or injection into or near major peripheral nerves or blood vessels, since such injections may produce neurovascular damage; particular care should be taken with IV administration because of the possibility of thrombophlebitis
• Skipping doses or not completing the full course of therapy may decrease the effectiveness of the immediate treatment and increase the likelihood that bacteria will develop resistance and will not be treatable by Penicillin G Potassium for Injection, USP, or other antibacterial drugs in the future
• In renal/hepatic impairment, reduce dose based on the severity of impairment

Clostridium difficile

• Clostridium difficile associated diarrhea (CDAD) reported; may range in severity from mild diarrhea to fatal colitis; CDAD must be considered in all patients who present with diarrhea following antibiotic use; may occur over two months after the administration of antibacterial agents
• If suspected or confirmed, discontinue ongoing antibiotic use not directed against C. difficile; administer appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile, and surgical evaluation should be instituted as clinically indicated

Pregnancy and Lactation

• Use may be acceptable during pregnancy
• Lactation: excreted in breast milk.