Amoxicillin Capsules 500mg x21 500mg Capsule POM

Amoxicillin 500mg Capsules

Clinical Overview

Amoxicillin 500mg is a broad-spectrum, semi-synthetic aminopenicillin antibiotic. It is commonly used in clinical practice for the treatment of a wide range of acute bacterial infections. As a beta-lactam antibiotic, it demonstrates activity against a variety of Gram-positive and Gram-negative pathogens.

How Amoxicillin Works (Mechanism of Action)

Amoxicillin is bactericidal in nature. It acts by inhibiting the biosynthesis of the bacterial cell wall during the stage of active multiplication.

1. Binding: The amoxicillin molecule binds to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall.
2. Inhibition: This binding inhibits the transpeptidase enzymes responsible for cross-linking peptidoglycan chains, which provide the cell wall with its structural integrity.
3. Lysis: The resulting weakened cell wall is unable to withstand internal osmotic pressure, leading to cell swelling, rupture (lysis), and bacterial death.

What Amoxicillin Is Used For (Licensed Indications)

Licensed indications for Amoxicillin 500mg Capsules include:

• Respiratory Tract Infections: Including acute sinusitis, community-acquired pneumonia, and acute exacerbations of chronic bronchitis.
• Dental Infections: Severe dental abscesses with spreading cellulitis.
• Urinary Tract Infections: Including acute cystitis and asymptomatic bacteriuria in pregnancy.
• Eradication of H. pylori: Used in combination with a proton pump inhibitor and another antibiotic for the treatment of peptic ulcers.

How to Take Amoxicillin (Dosage and Administration)

The dosage of Amoxicillin is dependent on the type and severity of the infection, as well as the patient's age and renal function.

• Standard Adult Dose: Typically 250mg to 500mg taken three times daily (every 8 hours).
• Course Duration: Completion of the prescribed course is recommended to reduce the risk of antimicrobial resistance.
• Method: Capsules should be swallowed whole with water. They may be taken with or without food.

Dosing should be determined by a healthcare professional based on clinical need.

Who Should Not Take Amoxicillin (Contraindications)

• Penicillin Allergy: Amoxicillin is strictly contraindicated in patients with a history of hypersensitivity to penicillin or other beta-lactam agents (e.g., cephalosporins, carbapenems).
• Glandular Fever: Amoxicillin should be avoided if infectious mononucleosis is suspected, as it frequently causes a maculopapular rash in these patients.

Side Effects and Safety Information

Like all medicinal products, Amoxicillin can cause adverse reactions, although not all patients will experience them. The frequency of these reactions is categorised where data is available.

Common (≥1/100 to <1/10):
Diarrhoea, nausea, and skin rash.

Uncommon (≥1/1,000 to <1/100):
Vomiting and urticaria (raised, itchy skin rash).

Rare (≥1/10,000 to <1/1,000):
Reversible changes in liver function tests (e.g., elevated transaminases).

Frequency Not Known (cannot be estimated from available data):

• Antibiotic-associated colitis (including pseudomembranous colitis), which may present with severe or persistent diarrhoea.
• Cholestatic jaundice and hepatitis.
• Severe cutaneous adverse reactions, including Stevens-Johnson syndrome and toxic epidermal necrolysis.
• Anaphylaxis and other serious hypersensitivity reactions.

Patients should be advised to seek immediate medical attention if symptoms of a severe allergic reaction occur, including difficulty breathing, swelling of the face or throat, or a widespread blistering skin rash.

Frequently Asked Questions

How does Amoxicillin work in the body?

Amoxicillin circulates in the bloodstream and diffuses into body tissues. Once it reaches the site of infection, it targets the bacteria's ability to maintain its protective outer wall, resulting in bacterial cell lysis and death.

How long does it take for Amoxicillin to work?

Amoxicillin begins acting on susceptible bacteria after administration; however, clinical response time varies depending on the infection and individual patient factors. Completion of the prescribed course is recommended to ensure adequate treatment and reduce the risk of antimicrobial resistance.

Should I take Amoxicillin with or without food?

Amoxicillin is stable in the presence of gastric acid and is well-absorbed by the gastrointestinal tract regardless of food intake. Taking it with food may reduce the likelihood of mild nausea.

How does Amoxicillin work for Pneumonia?

In cases of community-acquired pneumonia, Amoxicillin targets Streptococcus pneumoniae. It penetrates the lung tissue and pleural fluid, breaking down the bacterial cell walls that cause inflammation in the air sacs (alveoli).

How to dispose of Amoxicillin?

Unused antibiotics should never be disposed of via wastewater or household waste. They should be returned to a local pharmacy for safe clinical disposal to protect the environment from antibiotic contamination.

Clinical References and Further Information

For more detailed technical data, please refer to the following:

• NHS Medicine Guide: Amoxicillin
• Electronic Medicines Compendium (SmPC): Amoxicillin 500mg
• Patient Information Leaflet (PIL): Amoxicillin 500mg
• NICE British National Formulary (BNF) Guidance

Last Updated: April 2026