The Atacama is a spectacular place, but it is also a demanding one. The village sits at about 2,400 m, the geysers of El Tatio at around 4,200 m, the high lagoons at about 4,000 m, and the volcano summits at around 5,600 m, with air that is cold, dry and thin and sunshine that is very strong. Most visitors are fine with sensible preparation, and a little knowledge makes your trip more comfortable. This guide covers the basics, but it is not medical advice, so talk to your doctor before you travel, especially if you have any health conditions.
What altitude does
As you go higher, each breath holds less oxygen. Your body adjusts with faster breathing and a quicker heart rate, and over several days produces more red blood cells. Common symptoms of mild altitude sickness include headache, tiredness, nausea, poor sleep, dizziness and loss of appetite. They usually ease with rest, water and time. Serious symptoms, such as severe headache, confusion, difficulty walking, a persistent cough or breathlessness at rest, need immediate action: descend and seek medical help.
Ordering your days
The golden rule is to go up gradually. Spend your first day or two in and around the village at 2,400 m, with easy outings such as the Valle de la Luna, the Pukara de Quitor and the lagoons of the salt flat. Then move to the higher excursions: El Tatio and the high lagoons on day three or later, and volcano hikes such as Cerro Toco or Lascar only after several days. If you fly in from sea level, take extra care on the first night.
Drink water
The air is extremely dry, and you lose water through breathing and sweating without noticing. Drink small amounts frequently, aiming for a couple of litres or more a day, and carry a bottle on every excursion. Avoid or limit alcohol, particularly on arrival and before high-altitude days, as it dehydrates and affects sleep. Caffeine in moderation is fine for most people.
Eat and rest
Light, carbohydrate-rich meals are easier to digest at altitude than heavy, fatty ones. Eat small amounts before early tours, and bring snacks. Sleep may be lighter and broken in the first nights, which is normal. Rest in the afternoon if you can, particularly after dawn excursions. Move slowly at altitude, take breaks and do not rush up slopes.
Sun protection
The sun in the Atacama is intense, with very high ultraviolet levels. Wear a hat, sunglasses with good UV protection and sunscreen with a high factor, and reapply it often. Cover up with light long sleeves, since exposed skin burns fast. Remember that lips and the backs of the hands burn easily, and that the sun is strong even on cool days. Shade is rare on many trails.
Cold and wind
Nights and dawns are cold, with temperatures at El Tatio and the volcanoes often below freezing. Dress in layers, including a warm jacket, a hat, gloves and a scarf, and carry a windproof layer. Keep your feet warm and dry. Hot drinks help. If you are visiting in winter, expect colder conditions and bring more layers.
Who should take extra care
People with heart, lung or blood conditions, high blood pressure, severe anaemia, or who are pregnant should consult a doctor before travelling and before any high-altitude tour. Young children may be more affected by cold and altitude, and operators may have minimum ages for some outings. Ask your doctor about any medication you may wish to take, and make sure your insurance covers high-altitude activities and medical evacuation.
Tell your guide
Licensed guides are trained to recognise altitude problems and carry first-aid kits, and many carry oxygen. Tell them if you feel unwell, and follow their instructions to rest, turn back or descend. There is no shame in turning back, and conditions can change quickly in the highlands. Choose operators with good safety records, small groups and clear briefings.
Other health notes
The dry air can cause nosebleeds, cracked lips and irritated eyes, so use lip balm, a saline nasal spray and eye drops if needed. Dust and wind can irritate the throat, and a scarf or buff helps. Natural pools and lagoons can be very salty or warm, so follow rules and do not put your head under the water. Bring a small first-aid kit with any regular medicines, and wear sturdy shoes to avoid injuries on loose ground.