Antibiotics allergy
Vaccines, especially with live attenuated virus, may contain traces of antibiotics such as neomycin, gentamicin, streptomycin and polimixin B with the aim to avoid contamination among the manufacturing process. In case of allergy to such antibiotics, the most common clinical history regards local reactions as contact dermatitis, which require amounts of neomycin far higher than those normally found in vaccines to produce clinical manifestations, and which do not pose any contraindication to vaccinations17. In case of suspected allergy, patch tests are available and can be performed to confirm sensitization and choose alternative vaccines although re-vaccination is not contraindicated even in case of positive patch test results except for the very rare cases of anaphilaxys1,24. Commercially available haptens are kanamycin sulphate, polymyxin B, gentamycin and neomycin.