This is a research study on Altitude Illness. From the information collected and studied in this project we hope to learn more about Altitude Illness, including factors that may affect and prevent the development and progression of this condition. We hope to learn if the commonly used non-steroidal anti-inflammatory medication, ibuprofen can prevent altitude illness. Possible participants in this study are healthy adults who indicated they would like to participate, learn about altitude illness, and desire to hike Barcroft Peak. Stanford University researchers hope to enroll about 100 participants.

This study was designed to bring together elements of prior studies and go one step further for definitive data on several points. The trial will employ two pharmaceutical intervention arms, which will compare placebo (the standard of care - information on prevention of altitude sickness) with the widely used NSAID ibuprofen. We will also determine Optic Nerve Sheath Diameter (ONSD) measurements via ultrasound in both the control and interventional arms. We will accomplish these objectives with a prospective, double blinded view of a large population of hikers who are ascending at their own rate in a true hiking environment: The White Mountain Research Station Owen Valley Lab (OVL) and Bancroft Station (BAR).

Primary hypothesis: Ibuprofen 600 mg TID will be superior to placebo in decreasing both the incidence and severity of AMS in high altitude travel.

Inclusion Criteria:

1. Healthy Male or female volunteer
2. Age 18-65
3. Sea-level dwelling
4. Non pregnant
5. Have not been to high altitude in the past week
6. Can arrange for their own transportation to WMRS by friday evening the weekend of their study enrollment and are available the duration of the weekend of their study enrollment

Exclusion Criteria:

1. Age <18 or >65
2. Live at altitude > Sea Level +/- 1000'
3. Pregnant
4. Taking NSAIDs, Acetazolamide, or Corticosteroids
5. Allergic to NSAIDs or Aspirin, or have had adverse reaction to them in the past
6. Traveled or planning to travel to high altitude in the week prior to their enrollment.
7. Medical history of Brain Tumor, increased intercranial pressure, pseudotumor cerebri, ventricular shunts, loss of an eye, Asthma, HACE or HAPE.
8. Cannot arrange for their own transportation to WMRS or are unavailable for the duration of the weekend of their study enrollment

Participants meeting all inclusion criteria were analyzed

2 months