Precautions for Using Permanent Hair Dye

Permanent hair dyes alter hair color through chemical reactions; they deliver long-lasting results but should be used with caution. Here are the key points to keep in mind:


Permanent hair dyes alter hair color through chemical reactions; they deliver long-lasting results but should be used with caution. Here are the key points to keep in mind:

I. Preparations Before Use

Allergy test: Before first use, apply a small amount behind the ear or on the inner forearm 48 hours in advance and observe for any signs of an allergic reaction, such as redness, swelling, or itching.

Scalp examination: Ensure the scalp is free of breaks in the skin, inflammation, or eczema to prevent hair dye irritation from exacerbating symptoms.

Protective measures: Wear gloves when handling, and apply petroleum jelly along the hairline and around the ears to prevent skin contact with the hair dye.

II. Usage Process

Instructions: Mix the hair dye according to the instructions, apply evenly to the hair—avoiding the roots—and leave on for 20–30 minutes before rinsing thoroughly.

Environmental Safety: Ensure adequate ventilation, minimize inhalation of volatile gases, and avoid use in enclosed spaces.

III. Post-Use Care

Cleaning and Care: Wash your hair thoroughly with lukewarm water, avoid vigorously scratching the scalp, and use a color‑protecting shampoo to maintain your hair color.

Frequency control: Allow at least three months between hair dyeing sessions, and limit to no more than four applications per year to minimize cumulative damage to the hair.

IV. Special Populations

Contraindicated population: Pregnant women, breastfeeding mothers, children, and individuals with allergic constitutions should avoid use to prevent potential health risks.

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