Table 3 Risk factors for the development of drug allergy [16]

Patient-related factors

 •Age: young/middle-aged adults > infants/elderly

 •Gender: Women > men

 •Genetic polymorphisms

 •Viral infections: HIV, herpes viruses

 •Previous reaction to the drug

Drug-related factors

 •High molecular weight compounds and hapten-forming drugs are more immunogenic

 •Route: topical > IV/intramuscular > oral

 •Dose: frequent/prolonged > single dose