Aim : The aim of this study was to analyse the nature and incidence of adverse drug reactions to radiographic contrast media (ionic and non ionic) reported during a 3 year period in a tertiary care hospital in South India.

Methods : Adverse Drug Reactions (ADRs) to radiographic contrast media (ionic and non ionic) reported during a 3 year period to the pharmacovigilance centre, JIPMER, Pondicherry were retrospectively analysed for demographic profile, frequency, severity, causality and the temporal relationship of contrast administration to the occurrence of ADR.

Results : A total of 99 ADRs were spontaneously reported from 63 patients. It included 38 (60.3%) males and 25 (39.7%) females. The most common ADRs were nausea 26 (26.5%), vomiting 33 (33.7%) and rashes 30 (30.6%). As per Naranjo’s algorithm and WHO causality assessment, all reactions were ‘probable’. According to the Hartwig severity scale, 60 reactions were mild (60.6%), 34 (34.3%) were moderate and 5 (5.1%) were severe. There was no fatality reported. Adverse events required treatment in 38 (60.3%) patients. Most of the reactions (n=48, 76.2%) occurred immediately after contrast administration. Five (7.9%) reactions occurred during contrast administration and 10 (15.9%) reactions occurred within the next 30 minutes after contrast administration. Among the ADRs reported, the proportion of mild reactions were significantly higher in patients who received ionic contrast (n=42) than those who received non-ionic contrast (n=21) (p<0.05).

Conclusion : The common adverse reactions to contrast were nausea, vomiting and rashes. Most of the reactions occur immediately after administration of contrast and are of milder severity.