ORAPEN

Phenoxymethylpenicillin is a narrow spectrum antibiotic also commonly referred to as Penicillin V or Penicillin VK.

It is a phenoxymethyl analog of Penicillin G, or benzylpenicillin.

An Oral active naturally penicillin, phenoxymethylpenicillin is used to treat mild to moderate infections in the respiratory tract, skin, and soft tissues caused by penicillin G­-sensitive microorganisms.

Phenoxymethylpenicillin has also be used in some cases as prophylaxis against susceptible organisms.

While there have been no controlled clinical efficacy studies that were conducted, phenoxymethylpenicillin has been suggested by the American Heart Association and the American Dental Association for use as an oral regimen for prophylaxis against bacterial endocarditis in patients with congenital heart disease or rheumatic or other acquired valvular heart disease when they undergo dental procedures and surgical procedures of the upper respiratory tract, except for those who are at an elevated risk for endocarditis.

Indicated for the treatment of mild to moderately severe infections due to penicillin G­-sensitive microorganisms, with the use of bacteriological studies (including sensitivity tests) and clinical response.

Phenoxymethylpenicillin may be used for the treatment of: mild to moderate infections of the upper respiratory tract, scarlet fever, and mild erysipelas caused by Streptococcus without bacteremia mild to moderately severe infections of the respiratory tract caused by Pneumococcus mild infections of the skin and soft tissues caused by penicillin G-sensitive Staphylococcus mild to moderately severe infections of the oropharynx caused by Fusospirochetosis, including Vincent's gingivitis and pharyngitis, usually respond to oral penicillin therapy Off-label Indicated for use as prophylaxis against bacterial endocarditis in patients with congenital heart disease or rheumatic or other acquired valvular heart disease when they undergo dental procedures and surgical procedures of the upper respiratory tract.

**Label

Phenoxymethylpenicillin works against penicillin-sensitive microorganisms with bactericidal effects.

It targets the bacteria during its active multiplication stage by interfering with bacterial cell wall peptidoglycan synthesis.

In vitro, phenoxymethylpenicillin was shown to be active against staphylococci (except penicillinase-producing strains), streptococci (groups A, C, G, H, L and M), and pneumococci, as well as Corynebacterium diphtheriae, Bacillus anthracis, Clostridia, Actinomyces bovis, Streptobacillus moniliformis, Listeria monocytogenes, Leptospira, Neisseria gonorrhoeae, and Treponema pallidum.

PBP2' (penicillin binding protein 2') (Staphylococcus aureus) Inhibitor Penicillin-binding protein 1A (Clostridium perfringens (strain 13 / Type A)) Inhibitor D-alanyl-D-alanine carboxypeptidase DacB (Escherichia coli (strain K12)) Inhibitor + 1 more target.

Upon oral administration, phenoxymethylpenicillin is rapidly but incompletely absorbed.

The bioavailability of phenoxymethylpenicillin ranges from 25-60%.

Compared to the free acid form of the drug, the calcium or potassium salts of phenoxymethylpenicillin displays better absorption profiles.

It is reported that fasting state enhances the drug absorption.

The peak plasma concentrations of 200-700 ng/mL are achieved in 2 hours following an oral dose of 125 mg. Following an oral dose of 500 mg, the peak plasma concentrations of 3-5 μg/mL are reached in 30-60 minutes post-dose.

Following intravenous administration, the volume of distribution at steady state was 35.4 L.

Small amounts of the drug can be found in various tissues, with the highest amount found in the kidneys, with lesser amounts in the liver, skin, and intes­ tines.

Phenoxymethylpenicillin was found in the cerebrospinal fluid.

Phenoxymethylpenicillin was detectable in the placenta and human breast milk.

About 35-70% of an oral dose is metabolized to penicilloic acid, an inactive metabolite.

Small amounts of 6-aminopenicillanic acid have been recovered in the urine of patients on penicillin G. A small percentage of the drug appears to be hydroxylated into one or more active metabolites, which are also excreted via urine.

Hover over products below to view reaction partners Phenoxymethylpenicillin 6-aminopenicillanic acid Penicilloic acid.

While the drug is rapidly excreted, only 25% of the total dose is detected in the urine.

Renal excretion may be delayed in neonates, young infants, and patients with renal impairment.

Upon oral administration, the half-life is about 30 minutes.

It can last up to 4 hours in patients with renal impairment.

Improve decision support & research outcomes With structured adverse effects data, including: blackbox warnings, adverse reactions, warning & precautions, & incidence rates.

View sample adverse effects data in our new Data Library! See the data Improve decision support & research outcomes with our structured adverse effects data.

The oral

LD is >1040 mg/kg in rats.

Nausea, vomiting, black hairy tongue, and epigastric distress are common reactions to oral penicillins.

In rare cases, neuromuscular sensitivity and seizures may be seen with antibiotics and supportive treatments are advised and further drug absorption should be limited through induced emesis or gastric lavage, followed by administration of activated charcoal.

Severe hypersensitivity reactions, often leading to death, have been reported with penicillin therapies.

Although phenoxymethylpenicillin was shown to be excreted in human breast milk, the use of this drug in pregnant or nursing women is regarded generally safe.