Data from large clinical trials were used to determine the frequency of very common to rare undesirable effects. The frequencies assigned to all other undesirable effects (i.e., those occurring at <1/10,000) were mainly determined using post-marketing data and refer to a reporting rate rather than a true frequency.
The following convention has been used for the classification of frequency: Very common: ≥ 1/10; Common: ≥ 1/100 and <1/10; Uncommon: ≥ 1/1,000 and <1/100; Rare: ≥ 1/10,000 and <1/1,000; Very rare: < 1/10,000.
Infections and infestations:
Common: Mucocutaneous candidiasis.
Blood and lymphatic system disorders:
Rare: Reversible leucopenia (including neutropenia) and thrombocytopenia.
Very rare: Reversible agranulocytosis and haemolytic anaemia. Prolongation of bleeding time and prothrombin time.
Immune system disorders:
Very rare: Angioneurotic oedema, anaphylaxis, serum sickness-like syndrome, hypersensitivity vasculitis.
Nervous system disorders:
Uncommon: Dizziness, headache.
Very rare: Reversible hyperactivity and convulsions. Convulsions may occur in patients with impaired renal function or in those receiving high doses.
Adults: Very common: Diarrhoea.
Common: Nausea, vomiting.
Children: Common: Diarrhoea, nausea, vomiting.
All populations: Nausea is more often associated with higher oral dosages. If gastrointestinal reactions are evident, they may be reduced by taking Augmentin at the start of a meal.
Very rare: Antibiotic-associated colitis (including pseudomembranous colitis and haemorrhatgic colitis-see Precautions); Black hairy tongue; Superficial tooth discolouration has been reported very rarely in children. Good oral hygiene may help to prevent tooth discolouration as it can usually be removed by brushing.
Uncommon: A moderate rise in AST and/or ALT has been noted in patients treated with beta-lactam class antibiotics, but the significance of these findings is unknown.
Very rare: Hepatitis and cholestatic jaundice. These events have been noted with other penicillins and cephalosporins.
Hepatic events have been reported predominantly in males and elderly patients and may be associated with prolonged treatment. These events have been very rarely reported in children.
Signs and symptoms usually occur during or shortly after treatment but in some cases may not become apparent until several weeks after treatment has ceased. These are usually reversible. Hepatic events may be severe and in extremely rare circumstances, deaths have been reported. These have almost always occurred in patients with serious underlying disease or taking concomitant medications known to have the potential for hepatic effects.
Skin and subcutaneous tissue disorders:
Uncommon: Skin rash, pruritus, urticaria.
Rare: Erythema multiforme.
Very rare: Stevens-Johnson syndrome, toxic epidermal necrolysis, bullous exfoliative-dermatitis, acute generalised exanthemous pustulosis (AGEP) and drug reaction with eosinophilia and systemic symptoms (DRESS)
If any hypersensitivity dermatitis reaction occurs, treatment should be discontinued.
Renal and urinary disorders:
Very rare: Interstitial nephritis, crystalluria (see Overdosage).