Amoxicillin

Description

Amoxicillin capsules, USP are a semisynthetic antibacterial agent, specifically amoxicillin, which is an analog of ampicillin. It exhibits a broad spectrum of bactericidal activity against various Gram-positive and Gram-negative microorganisms. The chemical structure of amoxicillin is defined as (2S,5R,6R)-6-((R)-(-)-2-amino-2-(p-hydroxyphenyl)acetamido-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo3.2.0heptane-2-carboxylic acid trihydrate. The molecular formula for amoxicillin is C16H19N3O5S•3H2O, with a molecular weight of 419.45. Each capsule, characterized by a blue cap and pink body, contains either 250 mg or 500 mg of amoxicillin USP as the trihydrate. Inactive ingredients include D&C Red No. 28, FD&C Blue No. 1, FD&C Red No. 40, gelatin, magnesium stearate, microcrystalline cellulose, sodium lauryl sulfate, and titanium dioxide.

Uses and Indications

Amoxicillin capsules are indicated for the treatment of infections caused by susceptible strains of designated microorganisms. This medication is specifically indicated for the following conditions:

• Upper Respiratory Tract Infections of the Ear, Nose, and Throat

• Infections of the Genitourinary Tract

• Infections of the Skin and Skin Structure

• Infections of the Lower Respiratory Tract

• Helicobacter pylori Infection and Duodenal Ulcer Disease in adult patients only

Amoxicillin capsules should be utilized exclusively for the treatment or prevention of infections that are proven or strongly suspected to be bacterial in origin. This approach is essential to reduce the development of drug-resistant bacteria and to maintain the effectiveness of amoxicillin capsules and other antibacterial agents.

Dosage and Administration

In adults, the recommended dosage ranges from 750 mg to 1750 mg per day, administered in divided doses every 8 to 12 hours. For pediatric patients over 3 months of age, the dosage is 20 mg to 45 mg per kg per day, also given in divided doses every 8 to 12 hours. Healthcare professionals should refer to the full prescribing information for specific dosing regimens tailored to individual patient needs.

For neonates and infants aged 3 months or younger, the recommended dosage is 30 mg per kg per day, divided and administered every 12 hours.

In the treatment of Helicobacter pylori infection in adults, the following regimens are recommended: for triple therapy, administer 1 gram of amoxicillin, 500 mg of clarithromycin, and 30 mg of lansoprazole, all given twice daily (every 12 hours) for a duration of 14 days. For dual therapy, the regimen consists of 1 gram of amoxicillin and 30 mg of lansoprazole, each given three times daily (every 8 hours) for 14 days.

It is essential to reduce the dosage in patients with severe renal impairment, specifically in those with a glomerular filtration rate (GFR) greater than 30 mL/min.

Contraindications

Use is contraindicated in patients with a history of serious hypersensitivity reactions, including anaphylaxis or Stevens-Johnson syndrome, to amoxicillin capsules or other beta-lactam antibiotics, such as penicillins or cephalosporins. This contraindication is due to the potential for severe allergic reactions in these individuals.

Warnings and Precautions

Serious and occasionally fatal anaphylactic reactions have been reported in patients receiving penicillin therapy, including amoxicillin. In the event of an anaphylactic reaction, amoxicillin should be discontinued immediately.

Severe cutaneous adverse reactions (SCAR) may occur in some patients. It is essential to monitor patients closely for any signs of rash, and if the rash progresses, amoxicillin should be discontinued.

Drug-induced enterocolitis syndrome (DIES) has also been associated with the use of amoxicillin. Should this condition arise, it is imperative to discontinue amoxicillin and initiate appropriate therapeutic measures.

Clostridioides difficile-associated diarrhea (CDAD) can manifest in a spectrum ranging from mild diarrhea to severe, potentially fatal colitis. If a patient experiences diarrhea during treatment, a thorough evaluation is warranted to determine the appropriate course of action.

Side Effects

Serious adverse reactions associated with amoxicillin include anaphylactic reactions, which can be serious and occasionally fatal. Patients experiencing such reactions should have amoxicillin discontinued immediately. Severe cutaneous adverse reactions (SCAR) have also been reported; patients should be monitored closely, and amoxicillin should be discontinued if any rash progresses. Additionally, drug-induced enterocolitis syndrome (DIES) has been observed in patients using amoxicillin, necessitating discontinuation of the drug and appropriate therapeutic intervention if this occurs. Clostridioides difficile-associated diarrhea (CDAD) can manifest in a range of severity from mild diarrhea to fatal colitis, warranting evaluation if diarrhea develops.

Common adverse reactions reported in clinical trials include diarrhea, rash, vomiting, and nausea.

Patients with a history of serious hypersensitivity reactions, such as anaphylaxis or Stevens-Johnson syndrome, to amoxicillin capsules or other beta-lactams (including penicillins or cephalosporins) should exercise caution when considering amoxicillin therapy.

In cases of overdosage, interstitial nephritis resulting in oliguric renal failure has been documented in a small number of patients. Crystalluria, which in some instances has led to renal failure, has also been reported following amoxicillin overdosage in both adult and pediatric patients.

Drug Interactions

Co-administration of amoxicillin with probenicid is not recommended due to potential interactions that may affect the pharmacokinetics of amoxicillin.

When amoxicillin is used concurrently with oral anticoagulants, there is an increased risk of prolongation of prothrombin time. It is advisable to monitor prothrombin time closely in patients receiving this combination to ensure appropriate anticoagulation levels.

The concomitant use of amoxicillin and allopurinol has been associated with an increased risk of rash. Caution is advised when prescribing these medications together, and patients should be monitored for any signs of skin reactions.

Additionally, amoxicillin may reduce the efficacy of oral contraceptives. Patients using both amoxicillin and oral contraceptives should be informed of this potential interaction and may need to consider alternative or additional contraceptive methods during treatment.

Packaging & NDC

The table below lists all NDC Code configurations of Amoxicillin, the U.S. brand-name prescription product. Columns show Packaging, Formulation Type, and Active Ingredient Strength.

Pediatric Use

The safety and effectiveness of amoxicillin have been established for the treatment of upper respiratory tract infections, as well as infections of the genitourinary tract, skin and skin structure, and lower respiratory tract in pediatric patients. However, the safety and effectiveness of amoxicillin for the treatment of H. pylori infection have not been established in this population.

In pediatric patients aged 12 weeks or younger (3 months or younger), caution is advised due to incompletely developed renal function, which may delay the elimination of amoxicillin. Therefore, dosing should be modified accordingly in this age group to ensure safety and efficacy.

Geriatric Use

Clinical studies analyzing the response to amoxicillin in subjects aged 65 and older have not identified significant differences in efficacy or safety compared to younger patients. However, it is important to note that a greater sensitivity to the drug may be observed in some elderly individuals, which necessitates careful consideration during treatment.

Amoxicillin is primarily excreted by the kidneys, and the risk of toxic reactions may be heightened in patients with impaired renal function. Given that geriatric patients are more likely to experience decreased renal function, it is crucial to exercise caution in dose selection for this population. Monitoring of renal function is recommended to ensure appropriate dosing and to mitigate potential risks associated with renal impairment.

Pregnancy

Pregnant patients should be aware that amoxicillin is classified as Pregnancy Category B. Reproduction studies conducted in mice and rats at doses up to 2000 mg/kg, which is 3 and 6 times the human dose based on body surface area, did not demonstrate any evidence of harm to the fetus. However, there are no adequate and well-controlled studies in pregnant women.

Due to the limitations of animal reproduction studies in predicting human outcomes, amoxicillin should be used during pregnancy only if clearly needed. Healthcare professionals are advised to weigh the potential benefits against any possible risks when considering the use of amoxicillin in pregnant patients.

Lactation

Penicillins, including amoxicillin, have been shown to be excreted in human milk. The use of amoxicillin by nursing mothers may lead to sensitization of breastfed infants. Therefore, caution should be exercised when administering amoxicillin to lactating mothers.

Renal Impairment

Patients with renal impairment have no specific information regarding dosage adjustments or monitoring provided in the text. Therefore, healthcare professionals should exercise caution when prescribing this medication to individuals with reduced kidney function, as the absence of guidance necessitates careful consideration of potential risks and benefits. Regular monitoring of renal function may be advisable in these patients to ensure safety and efficacy.

Hepatic Impairment

Patients with hepatic impairment have not been specifically studied in relation to the use of this medication. Consequently, there are no established dosage adjustments, special monitoring requirements, or precautions outlined for individuals with compromised liver function. It is recommended that healthcare providers exercise caution when prescribing this medication to patients with hepatic impairment, given the lack of data on its safety and efficacy in this population. Regular monitoring of liver function may be prudent in these cases, although specific parameters are not defined in the available information.

Overdosage

In the event of amoxicillin overdosage, it is imperative to discontinue the medication immediately and implement symptomatic treatment alongside supportive measures as necessary.

A prospective study indicates that overdosages of amoxicillin below 250 mg/kg typically do not result in significant clinical symptoms. However, it is important to note that there have been reports of interstitial nephritis leading to oliguric renal failure in a small number of patients following overdosage. Additionally, crystalluria has been documented, which in some instances has progressed to renal failure in both adult and pediatric populations.

To mitigate the risk of crystalluria associated with amoxicillin overdosage, maintaining adequate fluid intake and promoting diuresis are essential. Renal impairment observed in these cases appears to be reversible upon cessation of the drug. It is also noteworthy that patients with pre-existing renal dysfunction may experience elevated blood levels of amoxicillin due to reduced renal clearance.

For patients experiencing severe overdosage, hemodialysis may be employed as a method to remove amoxicillin from circulation effectively. Healthcare professionals should remain vigilant in monitoring renal function and managing any complications that may arise during the course of treatment.

Nonclinical Toxicology

Long-term studies in animals have not been performed to evaluate the carcinogenic potential of the compound. While specific studies to detect the mutagenic potential of amoxicillin alone have not been conducted, data from tests on a 4:1 mixture of amoxicillin and potassium clavulanate provide relevant insights.

The combination of amoxicillin and potassium clavulanate was found to be non-mutagenic in both the Ames bacterial mutation assay and the yeast gene conversion assay. However, it exhibited weakly positive results in the mouse lymphoma assay, where the observed trend toward increased mutation frequencies occurred at doses that were also associated with decreased cell survival. In contrast, the mixture was negative in the mouse micronucleus test and the dominant lethal assay in mice.

Potassium clavulanate alone was evaluated in the Ames bacterial mutation assay and the mouse micronucleus test, yielding negative results in both assays.

In a multi-generation reproduction study conducted in rats, no impairment of fertility or other adverse reproductive effects were observed at doses up to 500 mg/kg, which is approximately twice the 3 g human dose based on body surface area.

Postmarketing Experience

Postmarketing experience has identified several adverse reactions reported voluntarily or through surveillance programs. Serious allergic reactions, including anaphylaxis, have been documented. Additionally, severe cutaneous adverse reactions (SCAR) such as Stevens-Johnson syndrome and toxic epidermal necrolysis have been observed.

Hepatic dysfunction, characterized by elevated liver enzymes and jaundice, has also been reported. Renal dysfunction, including cases of interstitial nephritis, has been noted. Hematologic reactions, such as thrombocytopenia, leukopenia, and hemolytic anemia, have been recorded as well.

Gastrointestinal disorders, specifically Clostridium difficile-associated diarrhea, have been reported among patients. Other reactions include seizures and hyperactivity.

Patient Counseling

Healthcare providers should advise patients that amoxicillin may be taken every 8 hours or every 12 hours, depending on the prescribed dosage. It is important to counsel patients that amoxicillin is a penicillin class drug, which can cause allergic reactions in some individuals.

Patients should be informed about the signs and symptoms of serious skin manifestations. They should be instructed to stop taking amoxicillin immediately and promptly report any signs or symptoms of skin rash, mucosal lesions, or other indications of hypersensitivity.

Additionally, healthcare providers should counsel patients that diarrhea is a common side effect associated with antibacterial drugs, typically resolving upon discontinuation of the medication. Patients should be made aware that they may develop watery and bloody stools (with or without stomach cramps and fever) even as late as 2 or more months after their last dose of the antibacterial drug. If such symptoms occur, patients should be advised to contact their physician as soon as possible.

It is essential to inform patients that antibacterial drugs, including amoxicillin, are intended solely for the treatment or prevention of bacterial infections and do not treat viral infections, such as the common cold. When prescribed amoxicillin for a bacterial infection, patients should be reminded that it is common to feel better early in the course of therapy; however, the medication must be taken exactly as directed. Skipping doses or failing to complete the full course of therapy may decrease the effectiveness of the immediate treatment and increase the likelihood of bacteria developing resistance, rendering them untreatable by amoxicillin or other antibacterial drugs in the future.

Storage and Handling

The product is supplied in a tight container to ensure integrity and stability. It should be stored at a temperature range of 20° to 25°C (68° to 77°F), with permissible excursions between 15° to 30°C (59° to 86°F) as defined by USP Controlled Room Temperature guidelines.

Additional Clinical Information

No further data are available.

FDA Insert (PDF)

This document is the official FDA-approved prescribing information for Amoxicillin as submitted by Sportpharm LLC. It includes detailed information about indications, dosage, contraindications, warnings, and clinical pharmacology.

View full prescribing information (PDF)