Nearly everyone feels below par for a week after a trek. Sore legs, a dry cough, deep tiredness and an enormous appetite are the normal aftermath of two weeks of hard walking at altitude, and they pass.
Occasionally something else is going on. Several infections that travellers pick up in Nepal take days or weeks to show themselves, by which time you are home, the trek feels long ago, and neither you nor your doctor immediately connects the two. This guide is about recognising the handful of symptoms that deserve attention — and making sure the right question gets asked.
This article is general information, not medical advice, and it is not a tool for self-diagnosis. If you are unwell after travelling, see a doctor and tell them where you have been.
Why Symptoms Can Appear After You Are Home
Every infection has an incubation period: the gap between exposure and the first symptom. For some it is hours. For others it is weeks, occasionally months.
| Infection | Usual incubation | Typical first symptoms | How it is caught |
|---|---|---|---|
| Bacterial travellers' diarrhoea | Hours to a few days | Sudden watery diarrhoea, cramps | Contaminated food and water |
| Dengue | 4 to 10 days | High fever, severe headache, pain behind the eyes, aching muscles and joints, rash | Day-biting mosquitoes; lowlands and cities, mainly monsoon to November |
| Cyclospora | About a week | Prolonged watery diarrhoea, fatigue, appetite loss | Contaminated food and water, mainly May to October |
| Giardia | 1 to 3 weeks | Bloating, sulphurous burps, loose greasy stools, on and off | Contaminated water and food |
| Typhoid | 1 to 3 weeks | Steadily rising fever, headache, abdominal pain, constipation or diarrhoea | Contaminated food and water |
| Scrub typhus | 1 to 3 weeks | Fever, headache, sometimes a small dark scab at the site of a mite bite | Mite bites in scrub and farmland, mainly monsoon and after |
| Malaria | A week to several months | Fever, chills, sweats, headache — often in cycles | Mosquitoes in the southern lowlands |
| Hepatitis A | 2 to 6 weeks | Tiredness, nausea, dark urine, yellow skin and eyes | Contaminated food and water; preventable by vaccine |
| Hepatitis E | 2 to 8 weeks | As hepatitis A | Contaminated water; no widely available vaccine |
| Rabies | Weeks to months after a bite | By the time symptoms appear it is too late — treatment must follow the bite | Dog and monkey bites and scratches |
The practical lesson: for at least three months after a trip to Nepal, any significant illness should prompt you to mention the trip.
Fever: The One Rule
A fever in the weeks or months after travel in South Asia needs a prompt medical assessment — the same day if it is high or you feel very unwell. Tell the doctor you have been in Nepal.
Most post-travel fevers turn out to be ordinary viral infections. But the serious causes — malaria, typhoid, dengue and others — are all treatable when diagnosed and can be dangerous when missed, and they cannot be told apart from flu without tests.
- If your trip included the lowlands — Chitwan, Bardia, Lumbini, the Terai, or overland travel to India — say so specifically. Malaria should be tested for, and it can appear months later, even if you took tablets.
- If you trekked only in the mountains, malaria is very unlikely, but typhoid and other infections are not ruled out.
- If you were in Kathmandu or Pokhara between July and November, mention dengue.
- Do not wait three days to see if it settles when the fever is high, comes with a rash, severe headache, confusion, bleeding, or yellow eyes.
- Note the pattern: when it started, how high, whether it comes and goes.
Which vaccines reduce these risks is covered in vaccinations for trekking in Nepal.
Stomach Symptoms That Persist
A stomach upset that began on the trek should be clearly improving within a few days of getting home. When it is not, the cause is usually a parasite, and the fix is usually simple.
| Pattern | Suggests | What to do |
|---|---|---|
| Loose stools, bloating, foul burps and wind, coming and going for weeks | Giardia | Stool test; a short course of a specific medicine |
| Watery diarrhoea with marked fatigue and no appetite, lasting weeks; trip was May to October | Cyclospora | Stool test — ask specifically, as it needs a special stain; a specific antibiotic |
| Blood or mucus in the stool; fever | Dysentery | See a doctor promptly |
| Loose stools after milk; otherwise well | Temporary lactose intolerance after infection | Avoid dairy for two to three weeks |
| Bloating and irregular bowels for weeks; tests clear | Post-infectious irritable bowel | Usually settles over months; see your doctor |
| Nausea, dark urine, pale stools, yellow eyes | Hepatitis | See a doctor the same day |
The rule of thumb: diarrhoea lasting more than two weeks needs a stool test. Tell the laboratory where you travelled. Background and trail treatment are in stomach illness on a Nepal trek.
Cough and Breathlessness
- A dry cough for one to three weeks after a high trek is the tail of the Khumbu cough and is expected.
- A cough lasting more than three weeks should be checked.
- Fever with coloured phlegm and chest pain suggests a chest infection.
- Breathlessness that is new or worsening after you have descended is not normal. Altitude-related lung problems improve quickly with descent; breathlessness that appears or persists at low altitude needs prompt assessment.
- Sudden breathlessness or sharp chest pain, particularly after a long flight, is an emergency — it may be a clot in the lung.
- Sharp pain in one spot on the chest wall when you breathe or cough may be a strained muscle or cracked rib from weeks of coughing.
More in Khumbu cough, colds and chest infections.
Legs, Feet and Skin
| Symptom | Likely cause | Action |
|---|---|---|
| One calf swollen, painful, warm or red | Possible deep vein thrombosis | Medical attention the same day |
| Both ankles mildly swollen for a few days | Fluid shifts after trekking and flying | Raise legs, keep moving; settles by itself |
| Numb or tingling toes or fingertips | Mild cold injury or nerve compression from boots | Usually recovers over weeks. See a doctor if skin blisters, blackens or stays numb beyond a month |
| Blister or cut with spreading redness, warmth, pus or red streaks | Skin infection | Doctor; antibiotics |
| Itchy bite marks that keep bleeding | Leech bites, on monsoon treks | Clean, keep covered; see a doctor if they become infected |
| A small dark scab with fever | Possible scrub typhus | See a doctor and mention it specifically |
| Itchy rash between toes or in skin folds | Fungal infection | Antifungal cream; keep dry |
| A knee or ankle still painful after two weeks | Tendon or ligament strain | Physiotherapy assessment |
| Black toenail | Bruising under the nail from descents | Harmless; the nail may fall off and regrow over months |
Any bite or scratch from a dog, monkey or other mammal during the trip that was not treated at the time still needs medical advice now. Rabies treatment after a bite is effective when given before symptoms and useless afterwards — do not let embarrassment or the passage of a couple of weeks stop you.
Altitude Symptoms That Should Be Gone
Altitude sickness is cured by descent. Headache, nausea and breathlessness from altitude should clear within a day or two of losing height. If you were evacuated or treated for HAPE or HACE, follow-up with a doctor is sensible before you go high again.
- Headache persisting for days at low altitude is not altitude sickness and needs assessment.
- Unsteadiness, confusion or memory problems after descent need urgent review.
- Blurred vision or a blind spot after a trek above 5,000 m may be a small bleed in the retina. These are common at extreme altitude and usually clear by themselves over weeks, but any change in vision should be examined by an eye specialist.
- Fingers and toes that went white and numb in the cold should have regained normal colour and feeling. Persisting changes need review.
If you had significant altitude illness on this trip, tell us before you book the next one. It does not rule out another trek, but it changes the itinerary — see altitude sickness in Nepal.
Mood, Sleep and Exhaustion
A flat, restless or tearful few days after a trek is common and passes — we cover it in post-trek meditation and the post-trek blues. Tiredness for a week is normal too.
- Exhaustion that is worsening after a week, especially with fever, weight loss, night sweats or stomach symptoms, may be a physical illness. See a doctor.
- Low mood or anxiety lasting more than two to three weeks deserves a conversation with your doctor.
- Intrusive memories or nightmares after a frightening event — an evacuation, an accident, a serious illness — are a recognised reaction and respond well to professional help.
What to Tell Your Doctor
Doctors at home see few travellers back from the Himalaya. Give them the facts and the diagnosis comes faster.
- Where you went: Nepal, with the regions — mountains only, or also the lowlands and which ones.
- Exact dates of travel and of return.
- How high you went and for how long.
- When the symptoms started and how they have changed.
- What you ate and drank: any untreated water, salads, street food.
- Insect and animal contact: mosquito bites, leeches, ticks or mites, and any bite or scratch from a dog or monkey.
- Fresh water exposure: swimming, rafting, wading.
- Illness during the trip and what you took for it, including any antibiotics.
- Vaccines you had and any antimalarials taken, and whether you finished them.
- Anyone else from the trip who is ill.
If your trek guide or operator has a record of what happened on the trail — a day you were ill, medication given, oxygen readings — ask for it. We are glad to provide this for our guests.
We Provide This Service: Pre- and Post-Trek Health Support
Green Compass Treks provides health support before, during and after every trek. The after part matters more than most people expect.
- A check-in before you leave Nepal. Your guide asks how you are, and anything that needs a doctor is picked up while you are still here.
- A clinic appointment arranged at a travel-medicine clinic in Kathmandu or Pokhara, with transport, for a fever, a stubborn stomach or a cough. Laboratories here test for giardia, cyclospora, typhoid and dengue routinely.
- Help with an animal bite: getting you to a clinic that stocks rabies vaccine, immediately.
- A summary of your trek on request — dates, altitudes, and anything your guide noted about illness or treatment — to give to your doctor at home.
- Support with insurance claims: the paperwork and letters your insurer asks for.
- Contact after you get home. If something develops later and your doctor wants details of the route or what happened, write to us.
We are not medical professionals and cannot diagnose — but we can make sure you reach one quickly, with the right information. Contact us at any time, including after your trip.
