Amoxicillin

Description

Amoxicillin for Oral Suspension is a semisynthetic antibacterial agent, specifically an analog of ampicillin, exhibiting a broad spectrum of bactericidal activity against various Gram-positive and Gram-negative microorganisms. The chemical structure is defined as (2S,5R,6R)-6-(R)-(-)-2-amino-2-(p-hydroxyphenyl)acetamido-3,3-dimethyl-7-oxo-4-thia-1-zabicyclo3.2.0heptane-2-carboxylic acid trihydrate. The molecular formula of amoxicillin is C16H19N3O5S•3H2O, with a molecular weight of 419.45.

For the oral suspension formulation, each 5 mL of the reconstituted suspension contains either 200 mg or 400 mg of amoxicillin as the trihydrate. Additionally, each 5 mL of both the 200 mg and 400 mg reconstituted suspension provides 0.1898 mEq (4.3635 mg) of sodium. The formulation includes inactive ingredients such as colloidal silicon dioxide, hypromellose, sodium benzoate, sucrose, trisodium citrate dihydrate, tutti frutti flavor, and xanthan gum.

Uses and Indications

Amoxicillin for Oral Suspension, USP is indicated for the treatment of infections caused by susceptible strains of designated microorganisms. This medication is utilized in the management of 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

To reduce the development of drug-resistant bacteria and to maintain the effectiveness of Amoxicillin for Oral Suspension, USP and other antibacterial agents, it is essential that this medication be used solely for the treatment or prevention of infections that are proven or strongly suspected to be caused by bacteria.

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 kilogram of body weight 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 upper limit of dosing is 30 mg/kg/day, divided and administered every 12 hours.

In the treatment of Helicobacter pylori infection in adults, two therapeutic regimens are recommended. The triple therapy consists of 1 gram of amoxicillin, 500 mg of clarithromycin, and 30 mg of lansoprazole, all administered twice daily (every 12 hours) for a duration of 14 days. Alternatively, the dual therapy includes 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 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 or other beta-lactams, such as penicillins or cephalosporins. This contraindication is based on 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 for Oral Suspension, USP. In the event of an anaphylactic reaction, it is imperative to discontinue the medication immediately.

Healthcare professionals should monitor patients closely for the development of severe cutaneous adverse reactions (SCAR). If any rash progresses, the use of Amoxicillin for Oral Suspension, USP should be discontinued without delay.

Additionally, drug-induced enterocolitis syndrome (DIES) has been associated with the use of amoxicillin. Should this condition arise, it is essential to discontinue Amoxicillin for Oral Suspension, USP and initiate appropriate therapeutic measures.

Clostridioides difficile-associated diarrhea (CDAD) can occur with amoxicillin treatment, presenting a spectrum of severity from mild diarrhea to potentially fatal colitis. If a patient experiences diarrhea during treatment, a thorough evaluation is warranted to determine the appropriate course of action.

Side Effects

Patients receiving Amoxicillin for Oral Suspension, USP may experience a range of adverse reactions. Common adverse reactions include diarrhea, rash, vomiting, and nausea.

Serious adverse reactions have also been reported. Anaphylactic reactions, which can be serious and occasionally fatal, have occurred in patients undergoing penicillin therapy, including those treated with amoxicillin. It is imperative to discontinue Amoxicillin for Oral Suspension, USP if such a reaction occurs. Additionally, severe cutaneous adverse reactions (SCAR) have been noted; patients should be monitored closely, and the medication should be discontinued if the rash progresses. Drug-induced enterocolitis syndrome (DIES) has been associated with amoxicillin use, necessitating discontinuation of the medication and appropriate therapeutic intervention if this condition arises. Clostridioides difficile-associated diarrhea (CDAD) can manifest, ranging from mild diarrhea to potentially fatal colitis, warranting evaluation if diarrhea occurs.

Patients with a history of serious hypersensitivity reactions, such as anaphylaxis or Stevens-Johnson syndrome, to amoxicillin or other beta-lactams (including penicillins or cephalosporins) should be closely monitored.

Overdosage of amoxicillin has been linked to interstitial nephritis, which may result in oliguric renal failure, as reported in a small number of patients. Crystalluria has also been documented, with some cases leading to renal failure in both adult and pediatric patients following overdosage.

Drug Interactions

Co-administration of Amoxicillin for Oral Suspension, USP with probenicid is not recommended due to potential interactions that may affect therapeutic outcomes.

When used concurrently with oral anticoagulants, Amoxicillin for Oral Suspension, USP may lead to an increased prolongation of prothrombin time. Clinicians should monitor prothrombin time closely and consider dosage adjustments of the anticoagulant as necessary.

The concomitant use of Amoxicillin for Oral Suspension, USP and allopurinol has been associated with an increased risk of rash. Patients should be monitored for dermatological reactions, and if a rash occurs, discontinuation of one or both medications may be warranted.

Additionally, Amoxicillin for Oral Suspension, USP may reduce the efficacy of oral contraceptives. Patients using hormonal contraceptives should be advised to consider alternative or additional contraceptive methods during and after treatment with Amoxicillin.

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 essential to exercise caution in dose selection for this population. Monitoring of renal function is recommended to ensure appropriate dosing and to mitigate the risk of adverse effects.

Pregnancy

Reproduction studies conducted in mice and rats at doses up to 2000 mg/kg, which is 3 and 6 times the human dose of 3 g based on body surface area, have shown no evidence of teratogenic effects or harm to the fetus due to amoxicillin. However, there are no adequate and well-controlled studies in pregnant women. Therefore, amoxicillin should be used during pregnancy only if clearly needed, as animal reproduction studies are not always predictive of human response. Healthcare professionals should weigh the potential benefits against the 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 lactating mothers may lead to sensitization of breastfed infants. Therefore, caution should be exercised when administering amoxicillin to a nursing woman.

Renal Impairment

There is no specific information available regarding dosage adjustments, special monitoring, or safety considerations for patients with renal impairment. Healthcare professionals should exercise caution when prescribing to patients with reduced kidney function, as the absence of detailed guidance necessitates careful clinical judgment. Regular monitoring of renal function may be advisable in this patient population.

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 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. Symptomatic treatment and supportive measures should be instituted as necessary to manage the patient's condition effectively.

A prospective study involving 51 pediatric patients at a poison-control center indicated that overdosages of amoxicillin below 250 mg/kg typically do not result in significant clinical symptoms. However, caution is warranted, as 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 in both adult and pediatric patients after amoxicillin overdosage, with some cases progressing to renal failure. To mitigate the risk of crystalluria, it is essential to maintain adequate fluid intake and promote diuresis.

Renal impairment resulting from overdosage appears to be reversible upon cessation of amoxicillin administration. It is important to note that patients with pre-existing renal impairment may experience elevated blood levels of amoxicillin due to decreased renal clearance. In such cases, hemodialysis may be employed to facilitate the removal of amoxicillin from the circulation.

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. Additionally, this combination was negative in the mouse micronucleus test and in the dominant lethal assay in mice.

Potassium clavulanate alone was tested 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 two times the 3 g human dose based on body surface area.

Postmarketing Experience

No specific postmarketing experience details have been reported. As such, there are no additional adverse events or rare case reports to summarize at this time.

Patient Counseling

Advise patients that amoxicillin for oral suspension may be taken every 8 hours or every 12 hours, depending on the prescribed dosage. Counsel patients that this medication contains a penicillin class drug, which can cause allergic reactions in some individuals. It is important to inform patients about the signs and symptoms of serious skin manifestations. Instruct patients to stop taking amoxicillin for oral suspension immediately and promptly report any signs or symptoms of skin rash, mucosal lesions, or other indications of hypersensitivity.

Patients should be made aware that diarrhea is a common side effect associated with antibacterial drugs, typically resolving upon discontinuation of the medication. However, patients may experience watery and bloody stools (with or without stomach cramps and fever) even as late as two months after completing the course of treatment. If such symptoms occur, patients should contact their physician as soon as possible.

Counsel patients that antibacterial drugs, including amoxicillin for oral suspension, are intended solely for the treatment or prevention of bacterial infections and do not address viral infections, such as the common cold. When prescribed amoxicillin for a bacterial infection, patients should be informed that it is common to feel better early in the treatment. However, it is crucial to take the medication exactly as directed. Skipping doses or failing to complete the full course of therapy may reduce the effectiveness of the treatment and increase the risk of bacteria developing resistance, making them untreatable by amoxicillin or other antibacterial drugs in the future.

It is preferable to refrigerate amoxicillin for oral suspension, although this is not mandatory. Patients should be instructed to shake the oral suspension well before each use and to keep the bottle tightly closed. When dosing a child with the suspension, a calibrated oral syringe should be used, and it is essential to rinse the syringe after each use. Patients should follow their doctor’s instructions regarding the appropriate amount to use and the duration of treatment required for their child. Any unused portion of the suspension should be discarded after 14 days.

Additionally, inform patients that the oral suspensions of amoxicillin do not contain phenylalanine, making them suitable for individuals with phenylketonuria.

Storage and Handling

The dry powder should be stored at a temperature range of 20° to 25°C (68° to 77°F), in accordance with USP Controlled Room Temperature guidelines. It is advisable to shake the container well before use. While refrigeration is preferable, it is not a requirement for storage. Once reconstituted, the suspension must be discarded after 14 days. To maintain product integrity, the container should be kept tightly closed when not in use.

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 Hikma Pharmaceuticals USA Inc.. It includes detailed information about indications, dosage, contraindications, warnings, and clinical pharmacology.

View full prescribing information (PDF)