Condition category
Injury, Occupational Diseases, Poisoning
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
Acute mountain sickness (AMS) is a common problem in people traveling higher than 2000 m in elevation. AMS involves headache, loss of muscle control, and can lead to brain swelling that causes death. Acetazolamide is a drug currently used to treat AMS. Recent research has shown that Ibuprofen may also prevent or reduce AMS. The goal of the study is to determine whether ibuprofen prevents AMS more effectively than current treatment.

Who can participate?
The study plans to enrol 350 non-Nepali male and female trekkers passing through the villages of Pheriche or Dingboche between the ages of 18-65, without headache and not already taking ibuprofen.

What does the study involve?
Trekkers will be recruited as they travel from either Pheriche or Dingboche on their way to Lobuje. They will be randomly allocated to take either ibuprofen or placebo (dummy) capsules. They will take the medication 18-24 hours prior to beginning their climb. Basic measurements will be taken before trekkers begin their climb, such as pulse rate, and an AMS questionnaire will be administered. After reaching the destination of Lobuje, the measurements will be taken again, and the AMS questionnaire will be administered again.

What are the possible benefits and risks of participating?
Participants may receive better treatment than standard care by participating in this study. The likelihood of a severe reactions to ibuprofen is uncommon, and participants will be removed from the study and provided with treatment if such a reaction occurs.

Where is the study run from?
The study is run by researchers at the Oxford University Clinical Research Unit (OUCRU) – Nepal; The Nepal International Clinic – Kathmandu, Nepal.

When is the study starting and how long is it expected to run for?
The study ran from October to November 2008.

Who is funding the study?
The Wellcome Trust (UK).

Who is the main contact?
The Clinical Trials Unit at the Oxford University Clinical Research Unit – Viet Nam
+84 839241983

Trial website

Contact information



Primary contact

Dr Buddha Basnyat


Contact details

GPO BOX 3596

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Randomised, double blind placebo controlled trial comparing Ibuprofen 600 mg three times per day versus placebo in the prevention of acute mountain sickness



Study hypothesis

Ibuprofen 600 mg twice daily (TID) given at least 18 - 24 hours in advance of ascent will be superior to placebo in decreasing both the incidence and severity of acute mountain sickness (AMS).

Ethics approval

Oxford Tropical Medicine Research Ethics Committee (OXTREC) (UK), pending as of 19/09/2008. Submitted for review on the 25/09/2008.

Study design

Prospective double-blind randomised placebo-controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


High altitude headache (HAH) and acute mountain sickness (AMS)


Ibuprofen 600 mg TID given at least 18 - 24 hours in advance of ascent, versus placebo. Participants will begin the study capsules 18 - 24 hours before they leave from Pheriche (4280 m) or Dingboche (4358 m), in order to reveal any significant acute adverse reactions before they leave for higher altitude; amounting to three doses before ascent. In the highly unlikely event of an adverse reaction, the participant will be in close proximity to study administrators and the Himalayan Rescue Association aid post, where the code can be broken for medical evaluation. Most participants will only take part of one day to arrive at the endpoint of Lobuje (4950 m), whereas some participants will stop at an intermediate altitude before ascending. Otherwise healthy participants without adverse reactions will continue on to the village of Lobuje, where they will again be evaluated on the first night of their arrival and the morning after (LLQ, visual analogue scale [VAS], pulse oximetry, intraocular ultrasound, ascent profile, infectious symptoms, side effects data, and compliance). After data collection the study will be completed for each participant.

Intervention type



Not Applicable

Drug names


Primary outcome measure

A diagnosis of AMS on the LLQ requires a score of three or greater with the mandatory presence of headache and at least one of the following symptoms: dizziness or light-headedness, fatigue, gastrointestinal (GI) symptoms (nausea/vomiting), or difficulty sleeping.

Secondary outcome measures

1. Oxygen saturation has a rough correlation with AMS symptoms, and will be measured with the use of a pulse oximeter, which is validated for use at high altitude (Nonin Onyx, Nonin Medical Products, Minneapolis, MN)
2. HAH incidence and severity will be scored based on a visual analog scale and the headache score identified on the designated LLQ score at a given altitude
3. Measurement of the optic nerve sheath diameter (ONSD) using bedside ultrasound have been shown to correlate with clinical and radiologic signs/symptoms of increased intracranial pressure

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Healthy men or women between the ages of 18 and 65 without any current illness
2. Travelling directly to either Mount Everest Base camp or Kala Patthar
3. Not using any drugs for the prevention of altitude sickness or headache

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Younger than 18 years old or are 65 years or older
2. Going to Gokyo, Chukung Ri, or Island Peak before going to Kala Patthar or Everest base camp
3. Have altitude sickness, more than one mild symptom on the Lake Louise Questionnaire (LLQ) (see below), or significantly depressed oxygen saturation (less than 75%)
4. If female, either known to be pregnant or cannot exclude the possibility of being pregnant, or have missed menses by over 7 days
5. A known drug allergy to ibuprofen/motrin, naprosyn/naproxen or aspirin
6. Already stayed the night at an altitude of 4500 metres/14,000 feet within the last 9 days
7. Have taken any of the following in the last 2 days: acetazolamide (Diamox®), steroids (dexamethasone/decadron, prednisone), theophylline or diuretics (Lasix®)
8. Have taken any of the following within the last 8 hours: ibuprofen/motrin, naprosyn/naproxen, aspirin or acetaminophen
9. Any serious intracranial abnormalities such as history of brain tumours or pseudotumour cerebri
10. Have any known severe uncontrolled headache syndrome

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre


Sponsor information


University of Oxford (UK)

Sponsor details

Clinical Trials and Research Governance
Manor House
John Radcliffe Hospital
United Kingdom

Sponsor type




Funder type


Funder name

The Wellcome Trust (UK) (grant ref: 077078)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes