* Damage to hair: Overexposure to the chemicals in hair dye, especially bleach, can weaken the hair shaft, leading to dryness, brittleness, split ends, and breakage.
* Uneven color or color buildup: The hair may absorb more color than intended, resulting in a darker or more intense shade than desired. With repeated over-processing, the color can become muddy or unnatural.
* Scalp irritation or burns: The chemicals in hair dye can irritate the scalp, causing redness, itching, burning, or even chemical burns in severe cases.
* Hair loss: In extreme cases of over-processing, the hair can become so damaged that it breaks off or falls out.
Always follow the manufacturer's instructions carefully and perform a strand test before applying hair color to the entire head to assess how your hair will react.