The following convention has been used for the classification of frequency: Very common >1/10; Common >1/100 and <1/10; Uncommon >1/1000 and <1/100; rare >1/10,000 and <1/1000; 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 haemolyticanaemia. 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 Co-amoxiclav at the start of a meal.
Uncommon: Indigestion. Very rare: Antibiotic-associated collitis (including pseudomembranous colitis and haemorrhagic colitis). Black hairy tongue.
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 generalized exanthemous pustulosis (AGEP); 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.