Meds and you

Updated 11 February 2013


Amoxicillin(also known as amoxycillin) is the active ingredient of Amoxil, Moxan, Maxcil, Moxypen and Zoxil.


Amoxicillin(also known as amoxycillin) is the active ingredient of Amoxil, Moxan, Maxcil, Moxypen and Zoxil.

Amoxicillin is also one of multiple active ingredients found in Suprapen, Megapen and Macropen (all amoxicillin + flucloxacillin), and Augmentin, Adco-Amoclav, Amoclan, AugMaxcil, Austell-co-Amoxiclav, Bio-Amoksiklav, Clamentin, Curam, Forcid, Ranclav, and Sandox-Co-Amoxyclav (all amoxicillin + clavulanic acid).

General information

Amoxicillin is a penicillin antibiotic. It is prescribed for the treatment of a wide range of bacterial infections caused by susceptible organisms, including middle ear infections, upper and lower respiratory tract infections, dental abscess, skin and soft tissue infections, and gonorrhoea. It is also used to prevent bacterial growth developing inside the heart in those who are at risk of such infection during certain surgical procedures. Amoxicillin is furthermore used along with other medication - often another antibiotic and a drug to reduce stomach acid secretion - to treat H. Pylori, a cause of stomach ulcers.

Amoxicillin can cause minor stomach upsets and a blotchy skin rash, a common unwanted effect which is not necessarily an indication of an allergic reaction. Should you develop a skin rash you should, however, consult your doctor to rule out the possibility of allergy. A penicillin allergy may lead to fever, swelling of the mouth and tongue, itching and associated breathing difficulties.

Antibiotic resistance - when a bacterium develops the ability to defend itself against the effect of an antibiotic - occurs frequently with amoxicillin. The most common causes for this are patients not completing prescribed antibiotic courses, allowing the bacteria to recover from treatment; and the use of antibiotics for non-bacterial infections such as cold and flu. Amoxicillin is not effective in treating a viral infection.

Oral contraceptives may not be as effective as usual while taking amoxicillin, so other methods of contraception is advised to avoid unplanned pregnancy.

How does amoxicillin work?

Amoxicillin function by changing the structure of the bacterial cell wall, allowing fluid to penetrate into the cell. As a result the bacterial cell literally ruptures.

Fast facts

Drug schedule: Schedule 4

Available as: Capsules, tablets, oral suspension and injection

What does it do? Amoxicillin is an antibiotic

Overdose risk: Low

Dependence risk: Low

Available as a generic? Yes

Available on prescription only? Yes

User information

Onset of effect: Within 2 hours

Duration of action: Up to 8 hours

Dietary advice: Amoxicillin can be taken with or without food. Taking it with a meal may, however, minimise stomach irritation, diarrhoea and nausea.

Stopping this medicine: Complete the full course as prescribed by your doctor, even if you feel better within a few days. Premature discontinuation may cause symptoms to recur, or cause bacterial resistance.

Prolonged use: Amoxicillin is generally given as short courses only. Prolonged use may increase the risk of a medicine-resistant infection.

Special precautions

Consult your doctor before using this drug if:

  • you are allergic to either penicillin or cephalosporins antibiotics, as there is a
  • possibility that you may be allergic to amoxicillin as well;
  • you have kidney or liver disease,
  • you have inflammatory bowel disease or ulcerative colitis,
  • you have any allergies,
  • you have glandular fever,
  • you have leukaemia, or
  • you are taking other medications.

Pregnancy: This medication is considered safe. You should, however, still consult your doctor before use.

Breastfeeding: Avoid. This medication is passed through breast milk and may affect your baby adversely. Consult your doctor before use.

Porphyria: This medication is safe to use.

Infants and children: This medication is safe for use in children at the recommended dose.

Elderly: No special precautions need to be taken.

Driving and hazardous work: No special precautions need to be taken.

Alcohol: No special precautions need to be taken.

Possible side effects

Side effect


Consult your doctor



Only if severe

In all cases

Mild diarrhoea



Nausea/ vomiting






White patches on tongue/ vaginal discharge/itch



Skin rash/ itch






Swollen mouth/ tongue






Unusual bruising






Dizziness/ fainting




Drug interactions:


Increased risk of skin rash


May affect the efficacy of amoxicillin. Take at least 2 hours apart


Reduce the efficacy of amoxicillin

Oral contraceptives

Possible reduced contraceptive efficacy. Another form of contraceptive is advised


Increased risk of amoxicillin toxicity


Possible reduced amoxicillin efficacy


Increased risk of warfarin toxicity

Overdose action

A small overdose is no cause for concern. In case of intentional large overdose, seek emergency medical attention.

Recommended dosage

Adults: 250-500mg every 8 hours.

Children under 20 kg: 10-25mg/kg 8 hourly

Children over 20kg: As for adults

This material is not intended to substitute medical advice, but is for informational purposes only. Please consult a physician for specific treatment and recommendations.


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