The mildest hypothermia can be treated without any help from a healthcare provider. Simply moving the patient to a warm, dry environment will usually do the trick.
While waiting for an ambulance, if possible, move the patient to a dry, warm environment. Remove any wet clothes. A dry patient with a thin blanket is better than a patient covered in multiple layers of wet clothing.
Moderate to severe hypothermia requires the intervention of a healthcare provider. Always call 911 for a patient who is confused or unconscious, even if the cause is unknown.