Amoxicillin
According to NHS medicines information, amoxicillin is a type of penicillin antibiotic used to treat bacterial infections such as chest infections (including pneumonia) and dental abscesses. It can also be used together with other antibiotics and medicines to treat stomach ulcers. Its FDA prescribing information states that it acts through inhibition of the bacterial cell wall building process, which kills susceptible bacteria while they are multiplying.
Key points
- Amoxicillin’s half-life is about 61 minutes, and roughly 60% of an oral dose is excreted in the urine within 6 to 8 hours.
- In triple therapy with clarithromycin and lansoprazole, amoxicillin’s frequently reported adverse events included diarrhoea (7%), headache (6%) and taste perversion (5%).
- Resistance to amoxicillin is driven mainly by beta-lactamase enzymes that break open its beta-lactam ring and inactivate the drug.
Amoxicillin alone and combined with clavulanic acid
Amoxil and Cenmox supply amoxicillin as a single active ingredient. Augmentin and Advent DT combine it with a second active ingredient, clavulanic acid, so their strength lines state both amounts separately.
Safety information
Amoxicillin is contraindicated in anyone who has had a serious hypersensitivity reaction, such as anaphylaxis or Stevens-Johnson syndrome, to amoxicillin or to another beta-lactam antibiotic including penicillins and cephalosporins, according to its FDA prescribing information. A high percentage of patients with mononucleosis who take amoxicillin develop a red, erythematous skin rash, so amoxicillin is not given to people with mononucleosis.
Further reading
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