The Mild Portable Hyperbaric Chamber is FDA Approved for the treatment of Acute Mountain Sickness (AMS). There are many symptoms of AMS but Headache leads the list of complaints, with about 70% of people who visit altitudes above 8000 feet suffering from at least a mild headache. Seven percent of visitors describe severe headaches, throbbing and bitemporal in nature, which are usually not responsive to over-the-counter medications.