Altitude Sickness in Nepal: Prevention, Diamox & Treatment in Kathmandu

Key Clinical Takeaways for Travelers in Nepal

• Kathmandu sits at 1,400m (4,600 ft) — you cannot get AMS in Kathmandu, making it the best place for pre-trek oximetry baselines and Diamox prescriptions.
• Lukla (2,860m) and Namche Bazaar (3,440m) are where initial mild AMS symptoms most frequently begin on the Everest Base Camp route.
• Never ascend to sleep at a higher altitude while experiencing any symptoms of AMS.
• Acetazolamide (Diamox) speeds up natural acclimatization; Dexamethasone masks/treats severe brain swelling during descent.

Clinical Stages of Altitude Illness in the Nepal Himalayas

Clinical Decision Flow: Self-Care vs. Clinic vs. Emergency

What causes altitude sickness on Nepal trekking routes?

As you ascend from Kathmandu (1,400m) toward high Himalayan passes like Thorong La (5,416m), Kala Patthar (5,545m), or Larkya La (5,106m), barometric pressure drops. Although the air still contains 21% oxygen, fewer oxygen molecules are pushed into your bloodstream with each breath.

Your body adapts over days by increasing respiratory drive, excreting bicarbonate through the kidneys, and producing more red blood cells. When ascent outpaces this physiological adaptation, fluid shifts into brain or lung tissues, causing Acute Mountain Sickness (AMS), High-Altitude Cerebral Edema (HACE), or High-Altitude Pulmonary Edema (HAPE).

Can I get altitude sickness medication (Diamox) in Kathmandu?

Yes. Acetazolamide (brand name Diamox, 250mg tablets) is readily available at Thamel Clinic following a brief physician screening. Acetazolamide works as a carbonic anhydrase inhibitor — it prompts the kidneys to excrete bicarbonate, lightly acidifying the blood and stimulating deeper, more regular breathing (especially at night when periodic breathing drops your oxygen saturation).

Because Acetazolamide is a sulfonamide derivative, a doctor should verify you have no history of severe sulfa antibiotic allergy, kidney disease, or liver impairment before you start prophylaxis.

• Prophylaxis (Prevention) Dose: 125 mg (half a 250mg tablet) every 12 hours, starting 24 hours before ascending above 2,800m and continuing until you reach maximum sleeping altitude and begin descending.
• Treatment Dose for Mild-Moderate AMS: 250 mg every 12 hours combined with rest or descent.
• Expected Harmless Side Effects: Tingling (paresthesia) in fingers, toes, and face; increased urination; carbonated drinks tasting flat.

What are the golden rules of acclimatization in Nepal?

Medication is never a substitute for a sensible ascent profile. Even with Diamox, rapid ascent on a rushed itinerary can trigger HAPE or HACE.

• Above 3,000m (9,800 ft), do not increase your sleeping elevation by more than 400–500 meters per day.
• Take a dedicated acclimatization rest night (two consecutive nights at the same altitude) every 900–1,000m of gain — on the EBC trek, this means mandatory two-night stops in Namche Bazaar (3,440m) and Dingboche (4,410m).
• Avoid alcohol, sleeping pills (benzodiazepines/zolpidem), and narcotic painkillers at altitude, as all three depress nighttime respiration.

Clinical References & International Guidelines

• Wilderness Medical Society (WMS) Clinical Practice Guidelines for Prevention and Treatment of Acute Altitude Illness (2024 Update)
• CDC Yellow Book: High-Altitude Travel & Altitude Illness
• Himalayan Rescue Association (HRA) Nepal — High-Altitude Medical Posts

Frequently Asked Questions

Key point: The fastest route to certainty in Kathmandu is a same-day confidential evaluation — most travelers leave Thamel Clinic with a clear answer, a treatment plan, or a firm rule-out rather than weeks of uncertainty.

Solo Traveler? What We Do Differently

• No companion needed. The whole visit — exam, tests, dispensing, documentation — is designed to be handled alone; nothing requires a second person.
• WhatsApp becomes your check-in line. Free post-visit messages mean "someone who knows your situation" is a text away — the closest thing to a travel partner for health questions.
• Share your location with the clinic. If you are being seen for something serious and traveling solo, tell the clinician where you are staying — knowing your hotel matters if follow-up contact fails.
• Emergency contact on file. Registration asks for an emergency contact — use it; a solo traveler benefits most from having someone reachable if things escalate.
• Documentation travels with you. Stamped English records mean your story does not depend on a companion remembering it — your records are your continuity.

Solo Female Traveler — What the Visit Looks Like

• No companion needed. The consultation happens one-on-one in a private room — nothing about the visit requires a second person in the room.
• A chaperone is a right, not a favor. You can request a staff chaperone for any part of the visit — it is offered, not something you have to ask for nervously.
• Sensitive concerns are routine. Sexual health, contraception, assault aftercare, pregnancy concerns — the clinician handles these the same way as anything else: privately, judgment-free, and without assumption.
• Your story stays yours. Nothing about the visit is shared with a partner, a family member, an employer, or anyone who is not you — no notification, no paperwork sent elsewhere.
• WhatsApp is your check-in line. Traveling alone means the WhatsApp follow-up channel is your "someone knows where I am" — use it.

If You're a Senior Traveler — What Changes for You

• Your medication list matters more. Multiple medications, comorbidities, and a longer history make the interaction check and the timeline more important — bring the list, not just the memory.
• Recovery may run slower. The same condition can take longer to resolve at 70 than at 30 — the clinician factors that into the plan and the expected timeline.
• The insurance check is different. Some travel policies cap coverage at 65 or 70 — the front desk can verify what your specific policy actually covers before the visit.
• Altitude and exertion read differently. The same trek that is routine for a 30-year-old can be a different clinical calculation for a senior — the risk profile is adjusted, not assumed.
• You are not "too old to travel." The visit is not a judgment about whether you should be here — it is about keeping the trip going safely, on your terms.

LGBTQ+ Travelers — What the Visit Looks Like

• No assumptions, no euphemisms. The clinician asks the clinical questions — not the identity questions — and uses the language you use for your body and your partners.
• Sexual health without the lecture. STI testing, PrEP/PEP questions, contraception, and exposure concerns are handled as clinical facts — not as commentary on who you are.
• Your partner is your partner. Whatever gender, whatever structure — the clinician asks about "your partner" and means it; the intake form does not prescribe a shape for your relationship.
• Documentation is neutral. The medical record uses clinically relevant terms, not identity labels — a visit for an STI test is documented as an STI test, not as a judgment about who you are.
• Discretion is the default. What you tell the clinician stays in the room — nothing is shared with partners, family, employers, or anyone who is not you.

Traveling With Kids — What Changes for Parents

• Children are seen here. The clinic sees children and adolescents — a child who needs a consult gets one; a family registering together can be seen as a group or individually.
• The parent is the historian. You describe the symptom; the clinician asks the questions a child cannot answer — timeline, appetite, behavior change, sleep, what you have already tried.
• The dose is different. Pediatric dosing is weight-based and often different from adult — bring the child's age and weight if you have it.
• The child's chart is yours. The medical record and the claim packet are issued in the child's name — useful for the pediatrician back home and for the insurer.
• It is not a pediatric hospital. Well-child checks and routine pediatric care are not the focus — acute illness, injury, and travel-health concerns are; anything beyond that is referred.

Immunocompromised Travelers — What Changes for You

• Your threshold for "come in" is lower. Chemo, transplant, HIV, high-dose steroids, and biologics all change how quickly a minor symptom becomes a serious one — what a healthy traveler would monitor for a week, you should bring in sooner.
• Your medication list is the visit. The interaction check, the timing of your immunosuppressants, and the antibiotic choice all depend on the full list — bring it, not just the highlights.
• Vaccine decisions are different. Live vaccines may be contraindicated; the clinician checks your status before recommending — what works for a healthy traveler may not apply to you.
• The antibiotic threshold is different. The same infection that a healthy traveler would treat with supportive care may warrant antibiotics for you — the clinician weighs that explicitly.
• You are not "too risky" to be seen. Immunocompromised travelers are seen here — the visit is calibrated to your risk, not dismissed because of it.

Pregnancy and Travel Health — What Changes for You

• Tell the clinician you are pregnant — always. Medication safety, imaging decisions, and treatment choices all depend on gestational age — it is the first thing that changes the plan.
• Altitude thresholds are different. Acetazolamide is generally avoided in pregnancy; the altitude plan is recalculated — do not rely on a healthy-traveler itinerary.
• Airline rules apply. Most airlines restrict travel after 36 weeks; some require a fit-to-fly letter after 28 — the documentation visit produces it if needed.
• Dehydration is a bigger risk. Traveler's diarrhea, vomiting, and heat exposure hit differently in pregnancy — the threshold for IV fluids and anti-emetics is lower.
• The visit is not a pregnancy consult. Routine prenatal care is not what this is — acute illness, travel-health concerns, and the "is this safe in pregnancy" question are; anything obstetric is referred.

What Travelers Say About Thamel Clinic

Verified patient reviews via Google Reviews — 4.9/5 across 340 reviews.

Thamel Clinic by the Numbers

If You Remember One Thing From This Page

Most cases seen at Thamel Clinic resolve the same day — the exceptions are almost always the ones that waited. If the red-flag description on this page applies to you, act now; if not, a $40 consult ends the uncertainty either way.

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