• Less than 5 years old.
• Hypersensitivity reactions to ragweed, any ingredient in pediculicide products, or chrysanthemums.
• An infection is likely occurring along with the lice infestation (excessive redness and inflammation of a widespread area, fever, pus formation, diarrhea, nausea, or vomiting).
• Current tumors.
• Pregnancy.
• Eyelids or eyebrows have lice.
• Lice have not been seen, uncertainty of lice infestation.