What to expect
A cool facial stimulus may briefly change autonomic response and alertness in some people. Effects vary and this is not a treatment for anxiety or cardiovascular disease.
A gentle test
Place a cool—not ice-cold—wet cloth on the face for 15–30 seconds. Breathe normally. Do not immerse the head or hold your breath.
Who should be cautious
People with heart disease, fainting, rhythm disorders or other significant conditions should consult a clinician before experimenting.
Important: Practical suggestions are for education and self-observation and do not replace medical care.