Health is very important factor before trekking. So staying healthy makes trekker complete their journey and have great adventure.


Making a point of washing your own hands frequently can also help prevent illness. The if you are tiny amounts of water that might cling, Africa or dishes and glasses washed in untreated water are not likely to make you sick, and drying the dishes can eliminate this problem. In general, the likelihood of becoming ill is re­lated to the amount of contamination you ingest at a given time. Your efforts to cut down eating contaminated food will likely decrease your exposure to disease-causing organisms, but you will not have control over every situation. For this reason, it is necessary to know how to treat diarrhea once it occurs.


One of the major medical advances of West­ern countries was to develop a sure way of keeping human waste out of the water supply. This problem has not been solved in Nepal, and all water must be viewed as potentially contaminated. Obviously, some urban water may be extremely contaminated, and some mountain water may be almost pure, but it is better to disinfect all water in Nepal be­fore drinking it. In recent years bottled water has become widely available in Nepal, with porters even carrying water in plastic bottles high into trekking areas. There is no quality control over the production of bottled water in Nepal, and preliminary studies have shown that some brands of bottled water are contaminated with bacteria that can cause diarrhoea.

Water Purification

While there is no con­sensus on the best method of purifying water in all circumstances; the following section examines some of the considerations.


All of the stool pathogens (disease producers) are killed by boiling water. How­ever, there is still conflicting advice about how long it is necessary to boil water in order to make it safe.


As an alternative to boiling, chemicals can be added to water to kill the pathogens. Iodine preparations and chlorine preparations are equally effective in killing the germs, but iodine is a bit more reliable in the field. There are three practical ways to carry iodine on a trek: as tetraglycine hydroperiodide tablets, Lugol’s solution and iodine crystals.

Tetraglycine hydroperiodide tablets are not available in Nepal, and can deteriorate in as little as six months in their original containers. Purchase bottles in your home country before travelling to Nepal. The tablets are convenient to use and not messy to carry. One bottle contains 50 tablets, which is enough to purify 50L of water.

Lugol’s solution is a water-based iodine concentrate; four to eight drops per litre of water are sufficient to make the water drink­able within 30 minutes. It is available in Kathmandu at supermarkets and most phar­macies. If you choose this method, bring along a small bottle with an eye dropper, as these are difficult to purchase in Nepal.

Iodine crystals have the advantage of being able to purify an almost unlimited amount of water. Four or five grams of iodine crystals in a 30ml glass bottle will purify water for months. The crystals will only dis­solve in water to a certain degree; once the water is saturated, it will not accept any more iodine. To make a saturated solution, fill the small bottle with water and wait 30 minutes. The resulting saturated solution may be added to your water bottle to purify the water for drinking; add 15ml to 30ml of the solution to your 1L water bottle and wait for 30 minutes before drinking. Refill the glass bottle at the same time, and after 30 minutes it will be ready to use again as well. Be particularly careful not to ingest an iodine crystal as this can be fatal.

If your main objection to using iodine is the taste, this can be completely eliminated by adding a small quantity of vitamin C (ascorbic acid) after you have waited for the iodine to work. Approximately 50mg of vitamin C when crumbled into 1L of water and shaken for a few seconds will com­pletely neutralise the iodine flavour in the water, making the water taste like pure spring water.

There has been some concern about the possible health consequences of using iodine over long periods of time or during preg­nancy. Although the use of iodine appears to have no serious consequences over long periods of time in the vast majority of people, there is evidence that the use of iodine daily for over three months could begin to have adverse effects on the thyroid gland. Iodine could also cause enlargement of the thyroid gland in a developing fetus.

How Long to Boil Water

There is no biological relationship between the temperature at which water changes from a liquid to a gas (100°C at sea level) and the temperature at which organisms in the water are killed. Boiling is just a convenient end point that is recognizable by anyone. There is an inverse relationship between heat and time: more heat, less time needed to kill; more time, less heat needed to kill. All of the pathogenic organisms start to be killed at 60°C or less. During the time it takes to go from 60°C to boiling, all organisms that could cause diar­rhoea are inactivated. All diarrhea-related bacteria are killed by one-minute exposure at 65°C. Hepatitis A virus is particularly resistant to heat, but it is killed with a one-minute ex­posure at 85°C, and longer exposures at lesser temperatures. Ciardia cysts are killed with five minutes exposure at 55°C. These figures demonstrate why the decreased boil­ing temperature associated with altitude does not decrease the effectiveness of boiling water for purification. Even at 5800m, the boiling temperature of water is still 81 °C. With the time it takes to bring water from 55° to 81 °C and back down to a drinkable temperature, all diarrhoea-causing organisms would be inactivated.

Water Filters

Filtering devices for disin­fecting water while travelling or trekking continue to be a popular consideration 4>r third-world travel. There are two types of filtering systems: those that provide mech­anical filtration only, based on the pore size, and those that expose the water to iod­ine in addition to filtration. The organizing that cause diarrhoea vary considerably in size. Protozoa, such as Giardia and amoebas, are seven to 10 microns in diameter. Bacteria are about 0.4 microns in diameter, and filtering devices have a pore size that ranges from 0.2 microns to one micron. Viruses can easily go through a pore opening at least four times larger than itself. A pore size of at least 0.2 microns is considered necessary to successfully filter bacteria and protozoa. Mechanical filtering alone cannot guarantee the elimination of viruses, so iodine resins have been added to some filters to deal with this problem. Good mechanical filters with iodine resins can produce safe water. Mech­anical filters alone would not be adequate for trekking in Nepal.


Unfortunately, just treating your water care­fully will not eliminate the chances of eat­ing disease-causing organisms. Throughout Nepal there is very little use of sewers to dispose of human waste. Thus, stool is found throughout the environment, and finds its way into your food. In the spring trekking season, flies are abundant and can be a major factor in spreading stool contamin­ation into restaurants and trekking kitchens. Lapses in kitchen hygiene are probably the main reason travellers become ill. Food prepares make basic errors in the kitchen, such as the preparation of raw meat on the same counters as other foods, failure to wash kitchen surfaces regularly, and not washing their hands after going to the toilet. Vegetables and fruits can also be contam­inated from the soil they are grown in, or from handling along the way. The general rule is to not eat any vegetables that cannot be peeled or freshly cooked unless they have been soaked in an iodine solution. Many restaurants in Kathmandu now soak their vegetables in an acceptable manner to make them safe, but if you are not sure, don’t eat them.

Try to avoid eating foods that are cooked once early in the day, and then reheated (perhaps inadequately) when you place your order. These foods, such as lasagna and quiche, can incubate bacterial growth throughout the day. Another food item that has been found to be highly associated with diarrhoea is the popular blended fruit-and- yogurt drink called lassi. The risk of illness is probably associated with not cleaning the blender between orders.

Common Ailments


Blisters on the feet result from re­peated rubbing of the skin against a hard surface (the inside of your shoe or boot). The superficial surface of the skin eventu­ally gets lifted off its base, and fluid collects in the resulting bubble. Blisters can usually be avoided by conscientious attention to your feet as you hike. Any sore spot on your foot while trekking should be investigated immediately, and some form of additional protection should be put over the area being rubbed. There are many commercial prod­ucts on the market to protect the feet from blisters in specific areas. Moleskin is the most popular item, but adhesive tape can also work well. Newer products, utilizing soft gels, have recently been added to the mix of products. Using a thin inner sock inside a thicker sock can provide a sliding layer that reduces the friction on the foot. Try not to begin a trek in brand-new shoes or boots.

Blisters are not infected when they first form, but after the bubble breaks, bacterial infection can develop. Try to wash the area and keep it clean. If swelling and redness develop, you will need to take oral antibiotics.

Trekkers’ Knee

Trekking in Nepal invari­ably involves multiple long ascents and des­cents. If your legs have not been gradually accustomed to walking uphill and downhill through training, there is a chance you will develop some degree of knee soreness after a long descent. The pain generally comes from mild trauma repeated thousands of times on the descent. The two areas most affected are the outer side of the knee, and under the kneecap. The pain can make it difficult to trek, and you may have to rest for several days before continuing. Anti-inflammatory pills are helpful, as are ski poles or a walking stick. The pain can take several weeks to go away completely, but there are no long-term consequences. If you have a history of knee pain while walking downhill, make sure you bring trekking poles. Studies have shown that trekking poles can take 20% to 30% of the weight off the knees.

Skin Diseases

Skin problems are common among travellers. Travellers generally are bothered by one of four major problems: allergic reactions, bacterial skin infections, fungal infections and skin mites (scabies).

A generalized rash due to an allergic reac­tion can consist of raised red spots in a var­iety of locations, often with a symmetrical distribution (equal on both sides of the body). One can also experience slightly raised flat red lesions that come and go rela­tively rapidly over a period of time (urticaria, or ‘hives’)- Either rash is usually caused by a new medicine, a new vaccine, or a new food. However, in many instances, it is im­possible to figure out just what triggered the rash. Travellers are often taking new medi­cations for the first time and may discover they have an allergy to one of these new drugs. In general, a rash scattered over most of the body is due to something taken intern­ally, and not to something you touched with your skin. The rash can be treated with anti­histamines in mild cases, or corticosteroids in more severe cases.

A painful, red swelling that keeps getting worse over several hours is probably a bac­terial skin infection. Staphylococcal in­fections that cause boils are common in travellers and account for about two-thirds of the skin problems in our clinic. If the boil is tense and painful, it may need to be opened and drained by a physician. Anti­biotics are necessary to get rid of the in­fection. Cephalexin is the best choice (if you are not allergic to penicillin). Azithromycin is a good alternative.

A round red patch, clearing in the centre and advancing at its edges, is usually a fun­gus and can be treated with an antifungal cream. These lesions can also occur in the groin and in the armpits. They are not painful, and do not cause swelling of the skin around the lesion. They can be treated with an antifungal cream.

Small, very itchy red spots, usually seen in clusters or in small straight lines, suggest an infestation with a tiny skin mite, causing a disease called ‘scabies’. This is not un­common in travellers, and is treated by a skin cream rubbed onto the whole body and left on for one day.

Many other skin conditions can arise, but we can’t list them all here. Just remember that skin conditions (such as psoriasis, eczema and allergic dermatitis) that could have occurred at home can coincidentally occur while travelling. When you have a new skin problem you need to consider whether it is travel-related.

Snow Blindness

Snow blindness is a tem­porary painful condition resulting from a sunburn of the clear surface of the eye (the cornea). It results from heavy exposure to ultraviolet radiation, almost exclusively in situations where someone is walking on snow without sunglasses. In Nepal it can af­fect people who don’t carry sunglasses, someone who has an accident on snow and loses their sunglasses, and porters, who generally don’t own sunglasses, or sell the ones they have been given. If you are in a party of trekkers attempting to cross a high pass covered with snow, try to make sure everyone has something to protect their eyes as they go.

The treatment is simply to try to relieve the pain. Cold cloths held against the out­side of the eyelids help relieve the pain and swelling. Antibiotic eye drops are not ne­cessary, and anaesthetic drops should be avoided as they slow down the healing and make the eyes vulnerable to other injuries. The cornea will be completely repaired within a few days. There are no long-term consequences of this injury.


Conjunctivitis is a bacterial or viral infection of the pink lining around the eye (the conjunctivae). Sufferers often awaken with a slightly swollen eye with in­creased redness in the pink areas, and occa­sionally some redness in the white part of the eye. Although it can be painful, it is more of a nuisance than anything else. Antibiotic eye drops can clear up bacterial infections within a day or so. Viral infections will clear themselves in a few days as well. Most of the infections seem to be bacterial, so using antibiotic eye drops makes sense. The infection almost always starts in one eye, but can spread to the other eye. Use the drops every two or three hours on the first day. As the infection improves, you can use the drops less often, and then stop as soon as the eye seems normal (usually two to three days).

If the eye is severely painful, vision is impaired or the white part of the eye is very red, seek medical help from an eye specialist. There are a few eye conditions travellers oc­casionally get that require specialized diag­nosis and treatment, such as uveitis, or herpes virus infections of the cornea.


The stomach and upper intestine are usually quite resistant to the normal stomach acid that aids in digestion. How­ever, raw areas in the stomach lining or in­testinal lining can develop, and these raw areas are very sensitive to acid, much as an abrasion on your skin would be more sensi­tive to acid than your intact skin would be. If these raw areas are in your stomach, we call the illness ‘gastritis’. If the raw area is in the intestine beyond the stomach we more often call it an ‘ulcer’. The main symptoms of gastritis or an ulcer are burning pain in the upper part of the abdomen. The pain can be treated with acid-blocking medi­cations, such as ranitidine or omeprazole. If you have any history of ulcer or gastritis, it would be a good idea to carry some of these medicines with you on a trek, in case your symptoms are stirred up by the combination of new organisms, stress and diet.


The veins of the lower in­testine form loops around the anus. Under conditions of strain (either constipation or diarrhoea), a loop of vein can become dis­tended and form a blood clot, which is ini­tially quite painful. The veins are called the haemorrhoidal vessels, and a clotted, dis­tended vein is called a haemorrhoid. If the swollen, tender vein is on the outside of the anus, it is called an ‘external haemorrhoid’, and if the vein is on the inside, popping out

occasionally, it is called an ‘internal haem­orrhoid’. External haemorrhoids can occa­sionally be cut open and the pain relieved, but this procedure is fairly painful, even with a local anaesthetic, and difficult to perform in the field. Soaking the haemorrhoid in hot water will quickly reduce inflammation and swelling, and within a few days the crisis will have passed. Internal haemorrhoids re­quire special treatment from a physician. However, external haemorrhoids are much more common among trekkers. The various creams that exist to treat haemorrhoids offer marginal benefit at best.

Kidney Stone

Over time, chemicals from the urine can begin to harden and form small stones in the collecting system of the kid­ney. Occasionally these stones dislodge and become wedged in the narrow channel of the urethra (the tube from the kidney to the bladder).

The pain associated with a stone in the urethra is excruciating. The pain usually starts rather abruptly in the back under the lowest ribs and spreads around to the groin in front. The pain is always on one side or the other, not both. Victims usually are very restless; unable to find a comfortable pos­ition, they often pace around or lean over a table or chair. Severe abdominal pain from some other cause usually causes people to want to lie still, so someone with severe pain on one side who wants to keep moving around probably has a kidney stone. The per­son may vomit from the severe pain. Blood is usually not visible in the urine, but can be found on microscopic examination.

Fortunately, 95% of kidney stones eventu­ally work their way down the urethra into the bladder, at which point the pain is com­pletely relieved. The stone is later urinated out without further difficulty. All one can do is try to control the pain, with inject able nar­cotics, if available, or whatever is at hand. Most of the time we allow three days or so for the stone to pass on its own, as long as there is no fever. The presence of a kidney stone and a fever may mean the kidney is infected, and this is a medical emergency since the infection cannot be cleared until the stone is removed. Evacuation is usually necessary for a kidney stone that doesn’t pass within one day. as the person usually cannot tolerate the pain.