** Thanks for contacting with your health concern. 1. As there is a history of visiting high altitude places, thus most probable diagnosis is reverse altitude sickness which happens when one moves from high to low altitude, since sometimes the body refuses to respond to environmental changes, especially if you have been at a high altitude for a long time. PS. Reverse altitude sickness is caused by thinning of blood and lack of oxygen in the body since when you are used to high altitudes and then returning to sea level, your body doesn t get enough oxygen causing rise in blood pressure and consequently you begin to breathe faster [same is happening with you] 2. Other symptoms associated with same are insomnia, headache, fatigue, shortness of breath and if symptoms are not serious you are likely to experience mild symptoms, but if left unchecked [since lack of oxygen and rise in blood pressure causes leakage of fluid from the blood vessels into the brain causing cerebral edema] it is a dangerous condition resulting in death. 3. If the symptoms worsen, call your doctor immediately [when you are at a lower latitude for the first time, supplemental oxygen is also important] as there are many people who have died neglecting it, since the condition is not irreversible and there are certain drugs like Acetazolamide/Dexamethasone which can help curb the symptoms but can only be prescribed by a certified physician. 4. the main treatment is to give your body time to adjust, next time you ascend from high to low altitude like: - maintain hydration - get enough sleep - Always descend gradually in order to give yourself enough time to adjust. - Low-calorie diet -