Symptoms of Altitude Sickness

The three ‘levels’ of altitude sickness are distinguished by the symptoms displayed by the sufferers. It is essential that your guide knows not only how to recognise AMS, but to know how severe it is too. As a back-up, it’s also useful if you know too. Here, then, are the symptoms of altitude sickness for each of the three levels.

Mild altitude sickness (mild AMS)

The symptoms of mild AMS are not dissimilar to the symptoms of a particularly vicious hangover. In other words, a thumping headache, nausea and a general feeling of lousiness. An AMS headache is generally agreed to be one of the most dreadful headaches you can get. It’s a blinding pain that thuds continuously at ever decreasing intervals. Only those who have bungee-jumped with a rope that’s ever-so slightly too long will know the intense, repetitive pain AMS can cause.

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Thankfully, the usual headache remedies should prove effective against a mild AMS headache. But do not continually take them. The guide needs to know that you’re suffering, and how severely. But it’s difficult for him to gauge that if you are permanently on painkillers. So do make sure you’re painkiller-free for at some of your time, so the guide can assess your condition properly.

As with a hangover, mild AMS sufferers often have trouble sleeping. Furthermore, when they do, that sleep can be light and intermittent. They can also suffer from a lack of appetite. Given the energy you’ve expended getting to altitude in the first place, both of these symptoms can seem surprising if you’re not aware of AMS. We strongly advise you not to take sleeping tablets. They tend to repress the respiratory system, which is the last thing you need! As for the lack of appetite, well I’m afraid you’ve just got to do your best to eat as much as you can. I know it’s horrible. It can feel like you’re a child again, with everyone encouraging you to eat food that you really don’t want to eat. But you’ll feel better if you do.

Moderate altitude sickness (moderate AMS)

Strolling on the Saddle

Walking slowly on the mountain can delay/prevent the onset of AMS.

Moderate AMS is more serious and requires careful monitoring of the sufferer to ensure that it does not progress to severe AMS. With moderate AMS, the sufferer’s nausea will lead to vomiting. In addition, the headache will not go away even after pain-relief remedies. What’s more,  the sufferer will appear to be permanently out of breath, even when doing nothing.

With moderate AMS, it is still possible to continue to the summit. But only after a prolonged period of relaxation that will enable the sufferer to make a complete recovery. Unfortunately, treks run to tight schedules and cannot change their itineraries mid-trek.

Whether you, as a victim of moderate AMS, will be given time to recover will depend largely upon how fortunate you are, and whether the onset of your illness happens to coincide with a scheduled rest day or not.

Severe altitude sickness (severe AMS)

With severe AMS, on the other hand, there should be no debate about whether or not to continue. If anybody is showing symptoms of severe altitude sickness it is imperative that they descend immediately. These symptoms include a lack of coordination and balance, a symptom known as ataxia.

A quick and easy way to check for ataxia is to draw a 10m line in the sand. Then simply ask the person to walk along it. If they struggle to complete this simple test, suspect ataxia and descend. (Note, however, that ataxia can also be caused by hypothermia or extreme fatigue. As such, ensure that the sufferer is suitably dressed in warm clothing and has eaten well before running the test).

Other symptoms of severe AMS

Other symptoms of severe altitude sickness include mental confusion, slurred or incoherent speech, and an inability to stay awake. (I know, your friend/spouse often behaves like this. But you, as their partner/bestie, will spot the difference before anyone else – including the sufferer him/herself.)

There may also be a gurgling, liquid sound in the lungs. This will often be combined with a persistent watery cough which may produce a clear liquid, a pinky phlegm or possibly even blood. There may also be a marked blueness around the face and lips, and a heartbeat that, even at rest, may be over 130 beats per minute. These are the symptoms of either HACO and HAPO, as outlined below.

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HACO (HACE) and HAPO (HAPE) on Kilimanjaro

HACE and HAPE on Kilimanjaro kill more people on the mountain than any other single thing. (Note that the Americans call it HACE and HAPE, but the Brits and others may know these twin conditions better as HACO and HAPO. That is simply because in the UK we spell it Oedema, while in America they prefer the simpler Edema.) But whatever you call it, it is these two conditions that kill. Both of them are the result of altitude sickness. Therefore, both of them are preventable, as long as you recognise and treat altitude sickness promptly.

Don’t just be concerned about your fellow trekkers either. Though the porters may climb the mountain all the time, and thus be pretty acclimatised already, they aren’t indestructible. And yes, I recognise that it’s not your responsibility to look after the welfare of your team, but your guides. But being in a position to recognise the symptoms and act is, at the very least, just being a decent and responsible member of society, no? After all, you don’t want to be like Peter McQueen, who wrote the following in his book In Wildest Africa at the beginning of the 20th century:

Poor Mapandi, a carrier whom I had noticed shivering with fever for the last day or two, stiffened, grew cold and died beside me in the mud.

High Altitude Cerebral Oedema / Edema (HACO /HACE)

Yellow Flower

St John’s Wort is useful for many ailments and flourishes on Kilimanjaro; it won’t be much use against HACE or HAPE, however.

HACO  is a build-up of fluid around the brain. It’s as serious as it sounds. It is HACO that is causing the persistent headache, vomiting, ataxia and the lack of consciousness. If not treated, death could follow in as little as 24 hours, less if the victim continues ascending.

High Altitude Pulmonary Oedema / Edema (HAPO / HAPE)

Just as serious, HAPO (HAPE in American English) is the accumulation of fluid around the lungs. It is this condition that is causing the persistent cough and pinkish phlegm. Once again, the only sensible option is to descend as fast as possible. In addition, one of the treatments outlined on p000 in the guide should also be considered.

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