Hair straightening treatments, whether chemical or heat-based, can have potential side effects. Common issues include dryness, brittleness, and breakage due to the weakening of hair fibers. Chemical treatments like relaxers can cause scalp irritation or burns if not applied correctly. Excessive heat from straightening tools can lead to split ends and dullness. It’s crucial to use high-quality products, follow professional guidance, and maintain a proper hair care routine to minimize these risks and ensure the health and integrity of your hair.