Amoxicillin

Amoxicillin is an antibiotic belonging to the Penicillin family. It works by inhibiting the formation of bacterial cell walls, preventing bacteria from growing and dividing until they die.

It's important to understand that Amoxicillin is a "bacteria-killing" drug (antibiotic), not an "anti-inflammatory" drug. It only works against bacterial infections — it has no effect on viruses (such as the common cold or influenza). Taking antibiotics for viral infections is not only ineffective but contributes to the global crisis of antibiotic resistance.

Amoxicillin has broad-spectrum coverage and is used to treat bacterial infections across multiple body systems.

🫁 Respiratory tract — Bacterial sinusitis / strep throat / bacterial bronchitis / middle ear infections (otitis media) / some cases of pneumonia

🦷 Oral and dental — Dental abscesses, post-extraction infections, bacterial gum infections

💧 Urinary tract — Certain urinary tract infections (cystitis)

🩹 Skin and soft tissue — Wound infections, abscesses, animal bite wounds (when combined with Clavulanic Acid)

🤢 Gastrointestinal — H. pylori infection in the stomach (used in combination with other medications such as PPIs for treating acid reflux and peptic ulcers)

Both contain Amoxicillin as the active ingredient, but with different formulations.

AMK — Amoxicillin alone — Pure Amoxicillin for treating standard bacterial infections where the bacteria haven't developed resistance. Suitable for strep throat, sinusitis, ear infections, and some urinary tract infections. Affordable and effective.

Augmentin — Amoxicillin + Clavulanic Acid — Includes Clavulanic Acid, which inhibits the Beta-lactamase enzyme that some bacteria produce to destroy Amoxicillin. This makes Augmentin effective against resistant bacteria. Ideal for more severe infections, resistant bacteria, or animal bite wounds.

In short: Standard infections → AMK is sufficient / More severe or potentially resistant infections → Augmentin

💊 Dosing — Typically taken three times daily (every 8 hours), e.g. morning, midday, and before bed, to maintain consistent blood levels / can be taken with or without food, but taking with food helps reduce nausea / for Augmentin specifically, taking at the start of a meal helps reduce diarrhoea

📅 Duration — Usually 5-7 days, or as prescribed by your pharmacist, depending on the type and severity of infection

⚠️ Most important rule — Always complete the full course. Even if you feel better after 2-3 days, do not stop early. Surviving bacteria can develop resistance and cause the infection to return. Antibiotic resistance is a global health crisis — completing your course is something everyone can contribute to.

🚫 Absolute contraindication — Anyone with a known Penicillin allergy must not take Amoxicillin. Allergic reactions include hives, facial swelling, lip and tongue swelling, and difficulty breathing. Always inform your pharmacist if you've ever had a Penicillin allergy.

Precautions — Kidney disease patients may need dose adjustments / Amoxicillin may reduce the effectiveness of certain contraceptive pills — use backup protection during the course / inform your pharmacist about all other medications you're taking, as interactions are possible

Amoxicillin has a strong safety profile, but some side effects can occur.

Common side effects — Diarrhoea (more common with Augmentin due to Clavulanic Acid irritating the gut) / nausea, vomiting / skin rash (not always an allergic reaction — some rashes from Amoxicillin are non-dangerous)

Allergic reactions requiring immediate action — Hives, skin swelling / facial, lip, or tongue swelling / difficulty breathing, chest tightness / if any of these occur, stop the medication immediately and go to the emergency room

This is a very common source of confusion, especially in Thailand where antibiotics are colloquially called "anti-inflammatory drugs."

Antibiotics (e.g. Amoxicillin, Ciprofloxacin) — Kill or inhibit the growth of bacteria. Used only for confirmed bacterial infections. No effect on viruses.

Anti-inflammatory drugs / NSAIDs (e.g. Ibuprofen, Naproxen) — Reduce inflammation, pain, swelling, and fever. Work on both infectious and non-infectious inflammation. See our pain relievers collection for more.

Why the confusion? — When bacteria cause an infection, the body responds with inflammation (pain, swelling, redness, heat). When antibiotics kill the bacteria, the inflammation resolves too — leading people to call antibiotics "anti-inflammatory drugs." But the antibiotic didn't directly reduce inflammation; it eliminated the cause.

Amoxicillin is not a cure-all. It should not be used in these situations.

❌ Common cold or influenza — These are viral infections. Antibiotics are completely ineffective.

❌ General sore throat — Most sore throats are caused by viruses, not bacteria. Don't take antibiotics without a proper diagnosis.

❌ Chronic cough not caused by bacteria — Coughs from allergies, asthma, or acid reflux don't need antibiotics.

❌ "Just in case" prevention — Never take antibiotics preventively without a medical indication. This is a major driver of antibiotic resistance.

Unnecessary antibiotic use is a leading cause of antibiotic resistance — a global health crisis. Always consult a pharmacist before using antibiotics.

Amoxicillin can be used alongside many medications, but some require caution.

✅ Generally safe together — Paracetamol, antihistamines, antacids such as Omeprazole

⚠️ Use with caution — Contraceptive pills (may reduce effectiveness — use backup protection) / Methotrexate — Amoxicillin may increase its levels / Warfarin — may need more frequent INR monitoring

Always inform your pharmacist about all medications you're currently taking before starting Amoxicillin.

Antibiotic resistance is one of the most serious global health threats. Improper antibiotic use is the primary driver.

🔬 How does resistance develop? — When you don't finish a course, the strongest bacteria survive, multiply, and pass on their resistance. Their offspring are now harder to treat. Using antibiotics when they're not needed (e.g. for viral colds) also accelerates this process.

What everyone can do — Complete every antibiotic course as prescribed / never buy antibiotics without professional guidance / never share your antibiotics with others / never use leftover antibiotics from a previous course