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Penicillin V Potassium Dosage

Medically reviewed by Drugs.com. Last updated on Sep 11, 2023.

Applies to the following strengths: 250 mg; 500 mg; 125 mg/5 mL; 250 mg/5 mL

Usual Adult Dose for Bacterial Infection

125 to 500 mg orally every 6 to 8 hours

Comments:

  • Therapy should be guided by bacteriological studies (including sensitivity tests) and clinical response.

Use: For the treatment of mild to moderately severe infections due to penicillin G-sensitive microorganisms

Usual Adult Dose for Streptococcal Infection

125 to 250 mg orally every 6 to 8 hours for 10 days

Comments:

  • Streptococci in groups A, C, G, H, L, and M are very sensitive to penicillin; other groups (including group D [enterococcus]) are resistant.

Use: For the treatment of streptococcal infections (without bacteremia) including mild to moderate infections of the upper respiratory tract, scarlet fever, mild erysipelas

Usual Adult Dose for Otitis Media

Streptococcal infections: 125 to 250 mg orally every 6 to 8 hours for 10 days
Pneumococcal infections: 250 to 500 mg orally every 6 hours until patient afebrile for at least 2 days

Uses:

  • Streptococcal infections: For the treatment of mild to moderate infections of the upper respiratory tract
  • Pneumococcal infections: For the treatment of mild to moderately severe infections of the respiratory tract, including otitis media

Usual Adult Dose for Upper Respiratory Tract Infection

Streptococcal infections: 125 to 250 mg orally every 6 to 8 hours for 10 days
Pneumococcal infections: 250 to 500 mg orally every 6 hours until patient afebrile for at least 2 days

Uses:

  • Streptococcal infections: For the treatment of mild to moderate infections of the upper respiratory tract
  • Pneumococcal infections: For the treatment of mild to moderately severe infections of the respiratory tract, including otitis media

Usual Adult Dose for Skin or Soft Tissue Infection

250 to 500 mg orally every 6 to 8 hours

Comments:

  • Culture and sensitivity studies recommended when treating suspected staphylococcal infections as reports indicate rising numbers of penicillin G-resistant strains.

Use: For the treatment of mild staphylococcal infections (penicillin G-sensitive) of the skin and soft tissues

Infectious Diseases Society of America (IDSA) Recommendations: 250 to 500 mg orally every 6 hours

Comments:
  • Recommended for the treatment of streptococcal skin infections
  • Current guidelines should be consulted for additional information.

Usual Adult Dose for Fusospirochetosis

250 to 500 mg orally every 6 to 8 hours

Comments:

  • For infections involving gum tissue, completion of essential dental care is recommended.

Use: For the treatment of fusospirochetosis (Vincent's gingivitis and pharyngitis), mild to moderately severe infections of the oropharynx

Usual Adult Dose for Rheumatic Fever Prophylaxis

125 to 250 mg orally twice a day

Comments:

  • Prophylaxis with oral penicillin on a continuing basis has been effective in preventing recurrence.
  • Since relatively penicillin-resistant alpha-hemolytic streptococci may be found in patients using continuous therapy for secondary prevention of rheumatic fever, other agents may be selected to add to their continuous prophylactic regimen.

Use: For the prevention of recurrence after rheumatic fever and/or chorea

American Heart Association (AHA) Recommendations: 250 mg orally twice a day

Duration of secondary prophylaxis (after last attack):
  • Rheumatic fever with carditis and residual heart disease (persistent valvular disease): 10 years or until 40 years of age (whichever is longer); sometimes lifelong prophylaxis
  • Rheumatic fever with carditis and no residual heart disease (no valvular disease): 10 years or until 21 years of age (whichever is longer)
  • Rheumatic fever without carditis: 5 years or until 21 years of age (whichever is longer)

Comments:
  • Recommended as secondary prevention of rheumatic fever (prevention of recurrence); continuous prophylaxis provides the most effective protection.
  • For high-risk patients, penicillin G benzathine given every 3 weeks may be more effective and is recommended; oral therapy can be used for prevention in lower risk patients whose compliance can be ensured.
  • Current guidelines should be consulted for additional information.

Usual Adult Dose for Tonsillitis/Pharyngitis

AHA Recommendations: 500 mg orally 2 to 3 times a day for 10 days

Comments:

  • Recommended for the treatment of streptococcal tonsillopharyngitis (primary prevention of rheumatic fever)
  • Current guidelines should be consulted for additional information.

Usual Adult Dose for Pharyngitis

IDSA Recommendations:

  • Patients with group A streptococcal pharyngitis: 250 mg orally 4 times a day or 500 mg orally twice a day for 10 days
  • Chronic pharyngeal carriers of group A streptococci: 12.5 mg/kg orally 4 times a day for 10 days
  • Maximum dose: 2 g/day

Comments:
  • Recommended oral regimen for group A streptococcal pharyngitis in patients without penicillin allergy
  • With 4 days of oral rifampin, recommended oral regimen for chronic carriers of group A streptococci
  • Current guidelines should be consulted for additional information.

Usual Adult Dose for Bacterial Endocarditis Prophylaxis

2 g orally 1 hour before procedure followed by 1 g orally 6 hours later

Comments:

  • The AHA recommends amoxicillin as the oral penicillin regimen for dental procedures; current guidelines should be consulted for additional information.

Use: For prophylaxis against bacterial endocarditis in patients with congenital heart disease or rheumatic or other acquired valvular heart disease for dental procedures or surgical procedures of the upper respiratory tract

Usual Adult Dose for Cutaneous Bacillus anthracis

US CDC Recommendations: 500 mg orally every 6 hours

Duration of Therapy:

  • Bioterrorism-related cases: 60 days
  • Naturally acquired cases: 7 to 10 days

Comments:
  • Recommended as an alternative oral regimen for the treatment of cutaneous anthrax without systemic involvement; recommended for penicillin-susceptible strains
  • Current guidelines should be consulted for additional information.

IDSA Recommendations: 500 mg orally 4 times a day for 7 to 10 days

Comments:
  • Recommended regimen for naturally-acquired cutaneous anthrax
  • Current guidelines should be consulted for additional information.

Usual Adult Dose for Anthrax Prophylaxis

US CDC Recommendations: 500 mg orally every 6 hours
Duration of prophylaxis: 60 days

Comments:

  • Recommended as an alternative oral regimen for postexposure prophylaxis; recommended for penicillin-susceptible strains
  • Current guidelines should be consulted for additional information.

Usual Adult Dose for Joint Infection

IDSA Recommendations: 500 mg orally 2 to 4 times a day

Comments:

  • Recommended as a preferred regimen for chronic oral antibacterial suppression for prosthetic joint infection; recommended for beta-hemolytic streptococci, penicillin-susceptible Enterococcus species, Propionibacterium species
  • Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Bacterial Infection

12 years or older: 125 to 500 mg orally every 6 to 8 hours

Comments:

  • Therapy should be guided by bacteriological studies (including sensitivity tests) and clinical response.

Use: For the treatment of mild to moderately severe infections due to penicillin G-sensitive microorganisms

American Academy of Pediatrics (AAP) Recommendations:
1 month or older: 25 to 75 mg/kg/day orally in 3 or 4 divided doses
Maximum dose: 2 g/day

Comments:
  • Recommended for mild to moderate infections; this drug is inappropriate for severe infections.
  • Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Streptococcal Infection

12 years or older: 125 to 250 mg orally every 6 to 8 hours for 10 days

Comments:

  • Streptococci in groups A, C, G, H, L, and M are very sensitive to penicillin; other groups (including group D [enterococcus]) are resistant.

Uses: For the treatment of streptococcal infections (without bacteremia) including mild to moderate infections of the upper respiratory tract, scarlet fever, mild erysipelas

Usual Pediatric Dose for Otitis Media

12 years or older:

  • Streptococcal infections: 125 to 250 mg orally every 6 to 8 hours for 10 days
  • Pneumococcal infections: 250 to 500 mg orally every 6 hours until patient afebrile for at least 2 days

Uses:
  • Streptococcal infections: For the treatment of mild to moderate infections of the upper respiratory tract
  • Pneumococcal infections: For the treatment of mild to moderately severe infections of the respiratory tract, including otitis media

Usual Pediatric Dose for Upper Respiratory Tract Infection

12 years or older:

  • Streptococcal infections: 125 to 250 mg orally every 6 to 8 hours for 10 days
  • Pneumococcal infections: 250 to 500 mg orally every 6 hours until patient afebrile for at least 2 days

Uses:
  • Streptococcal infections: For the treatment of mild to moderate infections of the upper respiratory tract
  • Pneumococcal infections: For the treatment of mild to moderately severe infections of the respiratory tract, including otitis media

Usual Pediatric Dose for Skin or Soft Tissue Infection

12 years or older: 250 to 500 mg orally every 6 to 8 hours

Comments:

  • Culture and sensitivity studies recommended when treating suspected staphylococcal infections as reports indicate rising numbers of penicillin G-resistant strains.

Use: For the treatment of mild staphylococcal infections (penicillin G-sensitive) of the skin and soft tissues

Usual Pediatric Dose for Fusospirochetosis

12 years or older: 250 to 500 mg orally every 6 to 8 hours

Comments:

  • For infections involving gum tissue, completion of essential dental care is recommended.

Use: For the treatment of fusospirochetosis (Vincent's gingivitis and pharyngitis), mild to moderately severe infections of the oropharynx

Usual Pediatric Dose for Rheumatic Fever Prophylaxis

12 years or older: 125 to 250 mg orally twice a day

Comments:

  • Prophylaxis with oral penicillin on a continuing basis has been effective in preventing recurrence.
  • Since relatively penicillin-resistant alpha-hemolytic streptococci may be found in patients using continuous therapy for secondary prevention of rheumatic fever, other agents may be selected to add to their continuous prophylactic regimen.

Use: For the prevention of recurrence after rheumatic fever and/or chorea

AHA and AAP Recommendations for Children: 250 mg orally twice a day

Duration of secondary prophylaxis (after last attack):
  • Rheumatic fever with carditis and residual heart disease (persistent valvular disease): 10 years or until 40 years of age (whichever is longer); sometimes lifelong prophylaxis
  • Rheumatic fever with carditis and no residual heart disease (no valvular disease): 10 years or until 21 years of age (whichever is longer)
  • Rheumatic fever without carditis: 5 years or until 21 years of age (whichever is longer)

Comments:
  • Recommended as secondary prevention of rheumatic fever (prevention of recurrence); continuous prophylaxis provides the most effective protection.
  • For high-risk patients, penicillin G benzathine every 3 weeks may be more effective and is recommended; oral therapy can be used for prevention in lower risk patients whose compliance can be ensured.
  • Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Tonsillitis/Pharyngitis

AHA Recommendations:

  • Children 27 kg or less: 250 mg orally 2 to 3 times a day
  • Children greater than 27 kg and adolescents: 500 mg orally 2 to 3 times a day
Duration of therapy: 10 days

Comments:
  • Recommended for the treatment of streptococcal tonsillopharyngitis (primary prevention of rheumatic fever)
  • Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Pharyngitis

IDSA Recommendations:
Patients with group A streptococcal pharyngitis:

  • Children: 250 mg orally 2 to 3 times a day
  • Adolescents: 250 mg orally 4 times a day or 500 mg orally twice a day
Duration of therapy: 10 days

Chronic pharyngeal carriers of group A streptococci: 12.5 mg/kg orally 4 times a day for 10 days
  • Maximum dose: 2 g/day

Comments:
  • Recommended oral regimen for group A streptococcal pharyngitis in patients without penicillin allergy
  • With 4 days of oral rifampin, recommended oral regimen for chronic carriers of group A streptococci
  • Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Pneumonia

Pediatric Infectious Diseases Society and IDSA Recommendations:
3 months or older: 50 to 75 mg/kg/day orally in 3 or 4 divided doses

Comments:

  • Recommended as a preferred oral regimen for community-acquired pneumonia due to group A streptococci; recommended for step-down therapy or mild infection
  • Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Bacterial Endocarditis Prophylaxis

12 years or older:

  • Less than 27 kg: 1 g orally 1 hour before procedure followed by 500 mg orally 6 hours later
  • At least 27 kg: 2 g orally 1 hour before procedure followed by 1 g orally 6 hours later

Comments:
  • The AHA recommends amoxicillin as the oral penicillin regimen for dental procedures; current guidelines should be consulted for additional information.

Use: For prophylaxis against bacterial endocarditis in patients with congenital heart disease or rheumatic or other acquired valvular heart disease for dental procedures or surgical procedures of the upper respiratory tract

Usual Pediatric Dose for Inhalation Bacillus anthracis

AAP Recommendations:
Up to 1 week of age:

  • Gestational age 32 to 37 weeks: 25 mg/kg orally every 12 hours
  • Term neonate: 25 mg/kg orally every 8 hours

1 to 4 weeks:
  • Gestational age 32 to 37 weeks: 25 mg/kg orally every 8 hours
  • Term neonate: 75 mg/kg/day orally in divided doses every 6 to 8 hours

1 month or older: 50 to 75 mg/kg/day orally in divided doses every 6 to 8 hours

Duration of Therapy:
Postexposure prophylaxis for B anthracis infection: 60 days after exposure

Cutaneous anthrax without systemic involvement:
  • Bioterrorism-related cases: To complete an antimicrobial regimen of up to 60 days from onset of illness
  • Naturally-acquired cases: 7 to 10 days

Follow-up for severe anthrax:
  • To complete a regimen of 10 to 14 days or longer (up to 4 weeks of age) or to complete a regimen of 14 days or longer (1 month or older)
  • Patients may require prophylaxis to complete an antimicrobial regimen of up to 60 days from onset of illness.

Comments:
  • Recommended as an alternative regimen for postexposure prophylaxis, the treatment of cutaneous anthrax without systemic involvement, and oral follow-up therapy for severe anthrax
  • Recommended as an alternative for penicillin-susceptible strains
  • Recommended for use with a protein synthesis inhibitor when used for follow-up therapy for severe anthrax (includes anthrax meningitis, inhalation anthrax, injection anthrax, gastrointestinal anthrax, and cutaneous anthrax with systemic involvement, extensive edema, or lesions of the head or neck).
  • Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Cutaneous Bacillus anthracis

AAP Recommendations:
Up to 1 week of age:

  • Gestational age 32 to 37 weeks: 25 mg/kg orally every 12 hours
  • Term neonate: 25 mg/kg orally every 8 hours

1 to 4 weeks:
  • Gestational age 32 to 37 weeks: 25 mg/kg orally every 8 hours
  • Term neonate: 75 mg/kg/day orally in divided doses every 6 to 8 hours

1 month or older: 50 to 75 mg/kg/day orally in divided doses every 6 to 8 hours

Duration of Therapy:
Postexposure prophylaxis for B anthracis infection: 60 days after exposure

Cutaneous anthrax without systemic involvement:
  • Bioterrorism-related cases: To complete an antimicrobial regimen of up to 60 days from onset of illness
  • Naturally-acquired cases: 7 to 10 days

Follow-up for severe anthrax:
  • To complete a regimen of 10 to 14 days or longer (up to 4 weeks of age) or to complete a regimen of 14 days or longer (1 month or older)
  • Patients may require prophylaxis to complete an antimicrobial regimen of up to 60 days from onset of illness.

Comments:
  • Recommended as an alternative regimen for postexposure prophylaxis, the treatment of cutaneous anthrax without systemic involvement, and oral follow-up therapy for severe anthrax
  • Recommended as an alternative for penicillin-susceptible strains
  • Recommended for use with a protein synthesis inhibitor when used for follow-up therapy for severe anthrax (includes anthrax meningitis, inhalation anthrax, injection anthrax, gastrointestinal anthrax, and cutaneous anthrax with systemic involvement, extensive edema, or lesions of the head or neck).
  • Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Anthrax Prophylaxis

AAP Recommendations:
Up to 1 week of age:

  • Gestational age 32 to 37 weeks: 25 mg/kg orally every 12 hours
  • Term neonate: 25 mg/kg orally every 8 hours

1 to 4 weeks:
  • Gestational age 32 to 37 weeks: 25 mg/kg orally every 8 hours
  • Term neonate: 75 mg/kg/day orally in divided doses every 6 to 8 hours

1 month or older: 50 to 75 mg/kg/day orally in divided doses every 6 to 8 hours

Duration of Therapy:
Postexposure prophylaxis for B anthracis infection: 60 days after exposure

Cutaneous anthrax without systemic involvement:
  • Bioterrorism-related cases: To complete an antimicrobial regimen of up to 60 days from onset of illness
  • Naturally-acquired cases: 7 to 10 days

Follow-up for severe anthrax:
  • To complete a regimen of 10 to 14 days or longer (up to 4 weeks of age) or to complete a regimen of 14 days or longer (1 month or older)
  • Patients may require prophylaxis to complete an antimicrobial regimen of up to 60 days from onset of illness.

Comments:
  • Recommended as an alternative regimen for postexposure prophylaxis, the treatment of cutaneous anthrax without systemic involvement, and oral follow-up therapy for severe anthrax
  • Recommended as an alternative for penicillin-susceptible strains
  • Recommended for use with a protein synthesis inhibitor when used for follow-up therapy for severe anthrax (includes anthrax meningitis, inhalation anthrax, injection anthrax, gastrointestinal anthrax, and cutaneous anthrax with systemic involvement, extensive edema, or lesions of the head or neck).
  • Current guidelines should be consulted for additional information.

Renal Dose Adjustments

Data not available

Liver Dose Adjustments

Data not available

Precautions

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Penicillin V potassium: 125 mg = 200,000 units; 250 mg = 400,000 units; 500 mg = 800,000 units

Administration advice:

  • May administer with meals, but blood levels slightly higher when administered on an empty stomach
  • In streptococcal infections, continue treatment for at least 10 days; take cultures after therapy completed to verify streptococci eliminated.

Storage requirements:
  • Oral solution: Store dry powder at 20C to 25C (68F to 77F); after reconstitution, store solution in refrigerator; discard solution after 14 days.
  • Tablets: Store at 20C to 25C (68F to 77F); keep bottle tightly closed.

Reconstitution/preparation techniques:
  • Oral solution: The manufacturer product information should be consulted.

General:
  • Dose should be determined based on sensitivity to infecting organisms and severity of infection and adjusted to patient's clinical response.
  • Culture and susceptibility information should be considered when selecting/modifying antibacterial therapy or, if no data are available, local epidemiology and susceptibility patterns may be considered when selecting empiric therapy.
  • This drug should not be used to treat patients with severe illness or with nausea, vomiting, gastric dilatation, cardiospasm, or intestinal hypermotility.
  • This drug should not be used during the acute phase of severe pneumonia, empyema, bacteremia, pericarditis, meningitis, or arthritis; it should not be used as adjunctive prophylaxis for genitourinary instrumentation/surgery, lower intestinal tract surgery, sigmoidoscopy, or childbirth.

Patient advice:
  • Avoid missing doses and complete the entire course of therapy.
  • Contact physician immediately if watery and bloody stools occur.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.