What client condition requires caution during treatment with heat sources?

Heat sensitivity is a critical condition that necessitates caution during treatments involving heat sources. Clients who have heat sensitivity may experience adverse reactions when exposed to warmth, such as an increase in redness, discomfort, or even more severe thermal injury. This condition can be due to previous skin treatments, certain medications, or underlying health issues that affect the skin's response to heat, making it crucial for estheticians to evaluate a client’s sensitivity before applying any heat-based treatments.

Understanding this sensitivity allows professionals to make informed decisions about the types of treatments applied, adjust temperatures accordingly, or choose alternative methods that minimize risk, ensuring a safe and effective experience for the client.