Please follow allergy test instructions included in the hair color kit (we don't carry samples) before applying any new color to your entire head. Allergies aren't to be taken lightly. Some allergies may develop over time with repeated exposure. Allergies can even build over a weeks time after exposure. Just because EcoColors is p-phenylenediamine (ppd) free, doesn't mean you won't react. There are other oxidative dyes present in nontoxic amounts that some individuals may be allergic to. Make sure to have a medical plan in place with your physician in case you do experience any kind of allergic symptom.