Most hikers will never experience altitude sickness, (sometimes called acute mountain sickness or AMS for short), because it typically only occurs at altitudes above 2,500m (8,300ft) or so. It’s caused by a decrease in the density of the air (the percentage of oxygen in the air doesn’t actually change much and remains the same to about ten times the height of Mt Everest!). With thinner air though, it becomes harder for the body to sustain mental and physical alertness.
Although we highly recommend training for your hiking trip, it won’t prevent altitude sickness, which can affect even the fittest athlete. It’s important for everyone to be aware of the symptoms of altitude sickness as they can affect anyone at any time, even if you’ve been fine up at altitude before. The main rule to remember is “Descend! Descend! Descend!” if any symptoms are present. If ignored, symptoms can very quickly go from bad to worse, so taking early action is the key. Descending to even just a slightly lower altitude can alleviate the symptoms and allow your body to adjust, before you carry on with your hike.
Symptoms of Altitude Sickness: What should you look out for and how do you manage it?
One of the things to pay attention to first and foremost is hydration - dehydration occurs faster at higher altitudes as water vapor is lost from the lungs and this, coupled with less oxygen, typically manifests itself as a headache. So the rule is - drink water like you’ve never drunk water before! Most of us are pretty bad at staying hydrated on a normal day in the office, let alone during exercise, but this is a great time to start a water drinking habit. You’ll find yourself needing the bathroom more frequently, but this is a good sign – you still need to drink water. Frequently!
- Lack of appetite, nausea, or vomiting
- Fatigue or weakness
- Dizziness or lightheadedness
- Pins and needles
- Shortness of breath upon exertion
- Persistent rapid pulse
- General malaise
- Peripheral edema (swelling of hands, feet, and face).
These symptoms are not life-threatening and can be managed by taking care to gain altitude slowly, hydrate frequently, avoid alcohol and by not overexerting yourself. If you’re usually one to dash up a trail as fast as you can, now is the time to slow it down, get your camera out and enjoy the view. There’s no hurry. Take it easy, you’re on holiday! If any of the symptoms appear then speak up – tell your guide or hiking partner.
Can’t sleep at altitude? You’re not alone.
At the other end of the spectrum, these milder symptoms, if ignored, can turn into life-threatening conditions very quickly. Edema (fluid accumulation in the tissues of the body) can occur either in the lungs (pulmonary edema) or in the brain (cerebral edema) and can cause death if untreated. The best way to avoid altitude sickness is to recognize the symptoms quickly, and descend. Our bodies have the ability to adapt, given time.
Being at high altitude can commonly result in disturbed sleep patterns or insomnia. This type of insomnia can occur in people who usually sleep well because the stages of deeper sleep are reduced at altitude. Periodic breathing, or Cheyne Stokes breathing, is common at high altitude, meaning alternating periods of deep breathing with shallow breathing, or even a pause in breathing, which can last up to 15 seconds! This is called apnea and may end with a gasp that may wake you up. Cheyne Stokes breathing occurs because the amount of carbon dioxide entering your body is lower than normal, switching off the drive to breathe, but then when your body recognizes you need oxygen you start breathing again, continuing the somewhat irregular cycle. Things will improve dramatically when you descend again if you’re experiencing these symptoms.
On our Active Adventures trips at altitude, we always schedule a number of acclimatization days, where we’ll hike up high during the day to give your body a taste of what’s to come, before descending again to sleep and recuperate. It’s the same technique used by mountaineers making their way up Mt. Everest – they’ll set up a series of camps and climb during the day, before heading back down to a lower altitude to sleep at night. It’s a technique that works well and gives you the chance to stop and explore a village, and spend some time relaxing in the mountains.
Our experienced Active Adventures Trip Leaders constantly monitor their hikers. We take things slowly, gradually making our way up and have a great support team who really know their stuff. One rule is always forefront in our minds – and that is “Descend! Descend! Descend!” If you’re on a trip anywhere in the world and feel unwell, don’t be shy – tell your guide.
Natural remedies and medicines
For centuries, indigenous people in South America have chewed coca leaves and consumed mate de coca to alleviate and prevent the symptoms of mild altitude sickness. Don’t worry, in this natural form, it doesn’t have the same effects as cocaine, which is a highly processed distillation of the alkaloids in the same plant. In fact you may come across mate de coca in Cuzco and it is perfectly fine to try some – they even give it out on the plane ride to Cuzco! You’ll also be able to try it in tea – coca tea is a popular refreshment and the more you drink the better you stay hydrated.
There are many over-the-counter drugs that you can buy now to help alleviate the symptoms of altitude sickness and these come under a couple of main brands: Diamox (an acetazolamide) and Dexamethasone (a steroid). We recommend consulting your travel doctor who will be able to prescribe you with the most suitable medication and do check with them what sort of side effects you may experience – it is common to experience hypersensitivity to sunlight, and a tingling sensation in the extremities.
Our trips and altitude
Our Peru trips visit higher altitude spots like Cuzco (3395m, 11,200ft) and Lake Titicaca (3811m, 12,500ft) and at these places it is not unusual to experience some mild symptoms of altitude sickness. In fact, we encourage you to arrive in Cuzco a few days before the trip starts if you can spare the time – it gives your body more time to adjust. Both the Classic Inca Trail and the Lares Trail get into heights of 2750m (9,000ft) right up to 4200m (13,780ft) at Dead Woman’s Pass. The distance of these hikes is only around 40km (25 miles), but it is challenging because of the altitude. Taking it easy, pacing yourself and drinking water will all help you take on the challenge with a smile on your face!
In Ecuador, the capital city of Quito sits at 2800m (9,200ft), so again it can be a bit of a shock when you land and take your first steps outside the airport, especially if they’re uphill! On the Tapir Ecuador adventure, we visit Cotapaxi Volcano and whilst we won’t make you climb it, we will drive you up to the refugio at 4723m (15,491ft), set you up with a bike and follow you back down the exhilarating ride as you descend 10,000ft! This is an awesome experience and often talked about as being the highlight of that trip.
And then of course there's Nepal, home of our Himalayas adventures, a destination that epitomizes hiking at altitude. Our Khumbu and Annapurna trips both reach altitudes of around 3750m, whilst the classic trek to Everest Base Camp (EBC) reaches 5,364m (17,598ft). For this reason, the EBC hike is spread out over 14 days, including acclimatization days, which gives your body time to adjust. Our guides will take great care of you and they carry portable tanks of oxygen that can be used to temporarily alleviate the symptoms of altitude sickness, if necessary. Many, many people do this trek successfully every year, reaching new heights in more ways than one. All you need to do is have good awareness, be sensible, speak up and take it easy. And if any symptoms present themselves – DESCEND – until you feel better. Then once your body has adjusted, you can carry on again.