Yes, you can use a toner if you have skin conditions like rosacea or eczema, but it's important to choose the right toner and approach cautiously. Opt for toners that are specifically formulated for sensitive skin, preferably alcohol-free and free from potential irritants. However, if you have severe rosacea or eczema, it's recommended to consult a dermatologist before introducing any new skincare product, including a toner. A professional can provide personalised guidance and recommend suitable products that won't exacerbate your condition.