Who should be cautious with this product or avoid it?

Because this is a fairly intensive capsaicin-based product, it is not the right choice for every situation.

• Sensitive skin. If your skin reacts easily to actives, do a patch test on a small area and wait several hours before a full application. If the test area becomes strongly red, itchy or painful rather than pleasantly warm, this format is probably too intense for you.
• Damaged skin. Never apply the cream to broken, scratched, freshly shaved or irritated skin, or over rashes — capsaicin on compromised skin feels dramatically stronger and can worsen irritation.
• Face and eye area. The cream is intended for body zones such as the neck, shoulders and back only. Keep it away from the face, eyes, nose and any mucous membranes, and wash your hands well after every use so you do not transfer it there accidentally.
• Children. Warming products of this intensity are formulated for adult skin; keep the tube out of children's reach.

Also think about timing: applying it right before a hot bath, sauna or intense sweating will amplify the burning sensation, so it is better used afterwards, once the skin has cooled. If you are pregnant or breastfeeding, or have chronic skin or circulatory conditions, consult a specialist before use. If at any point the warming stops feeling comfortable and the skin becomes red and reactive, discontinue use.