The frequency categories assigned to the adverse drug reactions as follows are estimates: for most reactions, suitable data for calculating incidence are not available. Adverse drug reactions identified through post-marketing surveillance were considered to be rare or very rare.
The following convention has been used for the classification of frequency: Very common ≥1/10, Common ≥1/100 to <1/10, Uncommon ≥1/1000 to <1/100, Rare ≥1/10,000 to <1/1000, Very rare <1/10,000.
Adverse reactions in association with allopurinol are rare in the overall treated population and mostly of a minor nature. The incidence is higher in the presence of renal and/or hepatic disorder.
Tabulated summary of adverse reactions: (see table).

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