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Pronunciation
(pen i SIL in vee poe TASS ee um)
Generic Available (U.S.)
Yes
Index Terms
Canadian Brand Names
Pharmacologic Category
Pharmacologic Category Synonyms
Use: Labeled Indications
Treatment of infections caused by susceptible organisms involving the respiratory tract, otitis media, sinusitis, skin, and urinary tract; prophylaxis in rheumatic fever
Use: Dental
Antibiotic of first choice in treatment of common orofacial infections caused by aerobic gram-positive cocci and anaerobes. These orofacial infections include cellulitis, periapical abscess, periodontal abscess, acute suppurative pulpitis, oronasal fistula, pericoronitis, osteitis, osteomyelitis, postsurgical and post-traumatic infection. Note: This agent is no longer recommended for dental procedure prophylaxis.
Pregnancy Risk Factor
B
Pregnancy Considerations
Adverse events have not been observed in animal studies; therefore, penicillin V is classified as pregnancy category B. Penicillin crosses the placenta and distributes into amniotic fluid. There is no evidence of adverse fetal effects after penicillin use during pregnancy in humans. Due to pregnancy-induced physiologic changes, some pharmacokinetic parameters of penicillin V may be altered in the second and third trimester. Higher doses or increased dosing frequency may be required.
Lactation
Enters breast milk/compatible
Breast-Feeding Considerations
Penicillins are excreted in breast milk. The manufacturer recommends that caution be exercised when administering penicillin to nursing women. Nondose-related effects could include modification of bowel flora and allergic sensitization.
Contraindications
Hypersensitivity to penicillin or any component of the formulation
Warnings/Precautions
Concerns related to adverse effects:
• Anaphylactoid/hypersensitivity reactions: Serious and occasionally severe or fatal hypersensitivity (anaphylactoid) reactions have been reported in patients on penicillin therapy, especially with a history of beta-lactam hypersensitivity, history of sensitivity to multiple allergens, or previous IgE-mediated reactions (eg, anaphylaxis, angioedema, urticaria). Use with caution in asthmatic patients.
• Superinfection: Prolonged use may result in fungal or bacterial superinfection, including C. difficile-associated diarrhea (CDAD) and pseudomembranous colitis; CDAD has been observed >2 months postantibiotic treatment.
Disease-related concerns:
• Renal impairment: Use with caution in patients with severe renal impairment; dosage adjustment recommended.
• Seizure disorders: Use with caution in patients with a history of seizure disorder; high levels, particularly in the presence of renal impairment, may increase risk of seizures.
Other warnings/precautions:
• Prolonged use: Extended duration of therapy or use associated with high serum concentrations (eg, in renal insufficiency) may be associated with an increased risk for some adverse reactions (neutropenia, hemolytic anemia, serum sickness).
Adverse Reactions
>10%: Gastrointestinal: Mild diarrhea, vomiting, nausea, oral candidiasis
<1%: Convulsions, fever, hemolytic anemia, positive Coombs' reaction, acute interstitial nephritis, hypersensitivity reactions, anaphylaxis
Drug Interactions
BCG: Antibiotics may diminish the therapeutic effect of BCG. Risk X: Avoid combination
Fusidic Acid: May diminish the therapeutic effect of Penicillins. Risk D: Consider therapy modification
Methotrexate: Penicillins may decrease the excretion of Methotrexate. Risk C: Monitor therapy
Mycophenolate: Penicillins may decrease serum concentrations of the active metabolite(s) of Mycophenolate. This effect appears to be the result of impaired enterohepatic recirculation. Risk C: Monitor therapy
Probenecid: May increase the serum concentration of Penicillins. Risk C: Monitor therapy
Tetracycline Derivatives: May diminish the therapeutic effect of Penicillins. Risk D: Consider therapy modification
Typhoid Vaccine: Antibiotics may diminish the therapeutic effect of Typhoid Vaccine. Only the live attenuated Ty21a strain is affected. Management: Vaccination with live attenuated typhoid vaccine (Ty21a) should be avoided in patients being treated with systemic antibacterial agents. Use of this vaccine should be postponed until at least 24 hours after cessation of antibacterial agents. Risk D: Consider therapy modification
Ethanol/Nutrition/Herb Interactions
Food: Decreases drug absorption rate; decreases drug serum concentration.
Storage
Refrigerate suspension after reconstitution; discard after 14 days.
Mechanism of Action
Inhibits bacterial cell wall synthesis by binding to one or more of the penicillin-binding proteins (PBPs); which in turn inhibits the final transpeptidation step of peptidoglycan synthesis in bacterial cell walls, thus inhibiting cell wall biosynthesis. Bacteria eventually lyse due to ongoing activity of cell wall autolytic enzymes (autolysins and murein hydrolases) while cell wall assembly is arrested.
Pharmacodynamics/Kinetics
Absorption: 60% to 73%
Distribution: Widely distributed to kidneys, liver, skin, tonsils, and into synovial, pleural, and pericardial fluids
Protein binding, plasma: 80%
Half-life elimination: 30 minutes; prolonged with renal impairment
Time to peak, serum: 0.5-1 hour
Excretion: Urine (as unchanged drug and metabolites)
Dosage
Usual dosage range:
Children <12 years: Oral: 25-50 mg/kg/day in divided doses every 6-8 hours (maximum dose: 3 g/day)
Children ≥12 years and Adults: Oral: 125-500 mg every 6-8 hours
Indication-specific dosing:
Children: Oral:
Pharyngitis (streptococcal): 250 mg 2-3 times/day for 10 days
Prophylaxis of pneumococcal infections:
Children <5 years: 125 mg twice daily
Children ≥5 years: 250 mg twice daily
Prophylaxis of recurrent rheumatic fever:
Children <5 years: 125 mg twice daily
Children ≥5 years: 250 mg twice daily
Adults: Oral:
Actinomycosis:
Mild: 2-4 g/day in 4 divided doses for 8 weeks
Surgical: 2-4 g/day in 4 divided doses for 6-12 months (after I.V. penicillin G therapy of 4-6 weeks)
Erysipelas: 500 mg 4 times/day
Periodontal infections: 250-500 mg every 6 hours for 5-7 days
Note: Efficacy of antimicrobial therapy in periapical abscess is questionable; the American Academy of Periodontology recommends use of antibiotic therapy only when systemic symptoms (eg, fever, lymphadenopathy) are present or in immunocompromised patients.
Pharyngitis (streptococcal): 500 mg 3-4 times/day for 10 days
Prophylaxis of pneumococcal or recurrent rheumatic fever infections: 250 mg twice daily
Dosing interval in renal impairment: Clcr <10 mL/minute: Administer 250 mg every 6 hours
Dental Usual Dosing
Note: No longer recommended for dental procedure prophylaxis
Orofacial infections: Oral:
Children <12 years: 25-50 mg/kg/day in divided doses every 6-8 hours (maximum dose: 3 g/day)
Children ≥12 years and Adults: 125-500 mg every 6-8 hours
Administration: Oral
Administer around-the-clock to promote less variation in peak and trough serum levels. Take on an empty stomach 1 hour before or 2 hours after meals, to enhance absorption, take until gone, do not skip doses.
Administration: I.V. Detail
pH: 6.0-8.5
Monitoring Parameters
Periodic renal and hematologic function tests during prolonged therapy; monitor for signs of anaphylaxis during first dose
Test Interactions
False-positive or negative urinary glucose determination using Clinitest®; positive Coombs' [direct]; false-positive urinary and/or serum proteins
Dietary Considerations
Take on an empty stomach 1 hour before or 2 hours after meals.
Patient Education
Take at intervals around-the-clock, preferably on an empty stomach (1 hour before or 2 hours after a meal). Maintain adequate hydration unless instructed to restrict fluid intake. May cause nausea, vomiting, or diarrhea. Report signs of opportunistic infection (eg, fever, chills, diarrhea, unhealed sores, white plaques in mouth or vagina, purulent vaginal discharge) or signs of hypersensitivity reaction (rash, hives, itching, swelling of lips, tongue, mouth, or throat).
Geriatric Considerations
Dosage adjustment in the elderly is usually not necessary.
Additional Information
0.7 mEq of potassium per 250 mg penicillin V; 250 mg equals 400,000 units of penicillin
Dental Health: Effects on Dental Treatment
Key adverse event(s) related to dental treatment: Oral candidiasis (prolonged use).
Dental Health: Vasoconstrictor/Local Anesthetic Precautions
No information available to require special precautions
Mental Health: Effects on Mental Status
Penicillins reported to cause apprehension, illusions, hallucinations, depersonalization, agitation, insomnia, and encephalopathy
Mental Health: Effects on Psychiatric Treatment
None reported
Nursing: Physical Assessment/Monitoring
Assess results of culture and sensitivity tests and patient's allergy history prior to starting therapy. Use with caution in presence of renal impairment. Monitor for hypersensitivity reactions and opportunistic infection (fever, chills, unhealed sores, white plaques in mouth or vagina, purulent vaginal discharge, fatigue).
Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Powder for solution, oral: 125 mg/5 mL (100 mL, 200 mL); 250 mg/5 mL (100 mL, 200 mL)
Tablet, oral: 250 mg, 500 mg
Pricing: U.S. (www.drugstore.com)
Solution (reconstituted) (Penicillin V Potassium)
250 mg/5 mL (100): $12.99
Tablets (Penicillin V Potassium)
250 mg (30): $13.99
500 mg (30): $25.99
References
Dajani AS, Bisno AL, Chung KJ, et al, “Prevention of Rheumatic Fever. A Statement for Health Professionals by the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease of the Council on Cardiovascular Disease in the Young, The American Heart Association,” Pediatr Infect Dis J, 1989, 8(5):263-6.
Slots J, Research, Science and Therapy Committee, “Systemic Antibiotics in Periodontics,” J Periodontol, 2004, 75(11):1553-65.
Wynn RL and Bergman SA, “Antibiotics and Their Use in the Treatment of Orofacial Infections, Part I and Part II,” Gen Dent, 1994, 42(5):398-402, 498-502.
International Brand Names
Lexi-Comp.com
Last full review/revision May 2011
Content last modified May 2011
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