If you find that your scalp becomes itchy or sweaty, then it is possible that the product containing sulphur could be causing this. This should only occur if you have used a product containing sulphur on your hair for at least 2 weeks before the first sign of dandruff appear. Sulfur-based products are not suitable for use on coloured or dyed hair as they can cause permanent damage to the colour treatment. The best course of action if dandruff appears after using a sulphur-containing shampoo would be to abandon using these types of products altogether and see what happens when you stop applying them over time! If this does not help, then try another non-sulphate based conditioner instead.