Pre-Expedition Medical Preparation — Tests, Vaccines, Training

Pre-expedition medical preparation for high-altitude trips is not a single visit to your family doctor the week before departure. It is a 3–6 month process covering baseline testing, vaccinations, chronic medication decisions, planning for comorbidities, and often a conversation about whether this particular expedition is safe for you. This guide provides: a complete 6-month pre-departure checklist, which tests to do (and which to skip), which vaccines are really needed for Nepal and Tanzania, and how to discuss diabetes, asthma, or hormonal contraception in the context of 6000 m.

Six-month pre-expedition checklist

1. 6 months before: consultation with expedition/travel medicine physician; start endurance training
2. 4 months before: baseline tests (blood work, resting ECG); dental review; specialist consultations for chronic diseases
3. 3 months before: first vaccinations (Hep A+B — 0/1/6 mo schedule); prescriptions for rescue drugs (acetazolamide, dexamethasone, nifedipine)
4. 2 months before: second vaccinations (typhoid, meningococcal); hypoxia test if indicated; insurance with helirescue
5. 6 weeks before: stress ECG (if >40 yrs or risk factors); last high-intensity training session
6. 4 weeks before: complete medical kit; check weight, blood pressure, wellbeing; intense aerobic base period
7. 2 weeks before: taper rest, avoid infections, final consultations
8. 1 week before: equipment list, dental visit if any doubts, test medical gear (pulse oximeter, headlamp, AED if you have one)

Baseline tests — what’s actually worth doing

Basic panel

• Complete blood count — especially Hb (normal >12 g/dL women, >13 g/dL men); low Hb combined with high expedition activity drastically shortens tolerance
• Fasting glucose + HbA1c — rules out undiagnosed diabetes
• Creatinine + eGFR — acetazolamide requires eGFR >30 mL/min; many rescue drugs cannot be used in renal insufficiency
• Liver enzymes (ALT, AST)
• TSH — hypothyroidism is a common unrecognized cause of fatigue, amplified at altitude
• Urinalysis
• Resting ECG — mandatory for all >35 yrs

Extended tests (conditional)

• Stress ECG (exercise test) — >40 yrs, family history of cardiac disease, hypertension, diabetes, smoking
• Spirometry — history of asthma or smoking
• Cardiopulmonary exercise testing (VO2max) — optional for those planning very high peaks; gives an objective measure of aerobic capacity
• Echocardiography — hypertension, prior arrhythmias, cardiac murmurs
• Hypoxia Altitude Simulation Test (HAST) — for asthma, COPD, cardiac disease; tests hypoxia tolerance by simulating FiO₂ 15% (equivalent to 2500 m)

Hypoxia test — is it worth it?

HAST involves breathing a 15% O₂ mixture for 20 minutes while monitoring saturation, heart rate, ECG, and symptoms. It simulates conditions at 2500 m — the threshold above which AMS becomes realistic in susceptible individuals.

When HAST makes sense:

• Patient with asthma, COPD, pulmonary hypertension
• History of HAPE/HACE without clear cause (fast ascent)
• Planned expedition >5000 m in person without prior high-altitude experience
• Aviation / high-altitude rescue work (service protocols)

Limitations: HAST predicts short-term tolerance but does not predict AMS/HAPE/HACE development over 24–72 h of actual acclimatization. A positive result does not exempt from the 300–500 m rule.

Vaccinations by destination

Nepal (EBC, Annapurna, Manaslu)

• Hepatitis A + B (combined TwinRix: 0/1/6 mo, or 0/7/21 days with 12-mo booster)
• Typhoid (Typhim Vi — 1 dose, 3-year protection)
• Cholera (Dukoral — 2 doses 1–6 weeks apart) — recommended for long expeditions
• Meningococcal ACWY — especially if staying in lodges with many people
• Pre-exposure rabies (3 doses in 0/7/21 days) — consider; immunoglobulin availability in Nepal is limited
• Japanese encephalitis (Ixiaro — 2 doses) — only if plan includes lowland Terai during monsoon
• Tetanus + diphtheria + pertussis — booster every 10 years

Tanzania (Kilimanjaro, Serengeti safari)

• Hepatitis A + B (TwinRix)
• Typhoid
• Yellow fever (Stamaril — 1 dose, lifetime validity since 2016) — MANDATORY for entry to Tanzania from at-risk-zone countries
• Malaria — pharmacological prophylaxis: atovaquone + proguanil (Malarone) 1 tablet daily; start 1–2 days before, continue 7 days after return. Alternative: doxycycline 100 mg/day (cheaper, phototoxic)
• Meningococcal ACWY — mandatory on some safari routes in the “meningitis belt”
• Pre-exposure rabies — consider

South America (Peru, Argentina — Cordillera, Aconcagua)

• Hepatitis A + B
• Typhoid
• Yellow fever — mandatory for some parts of Peru (Amazon); not required for typical high-altitude routes but a good option
• Rabies — consider
• Malaria is usually not a risk above 2500 m — unless plan includes lowlands

Chronic disease protocols

Hypertension

Altitude causes physiological blood pressure rise (sympathetic activation + polycythemia). For controlled hypertension: continue medications, monitor BP morning and evening. Caution with beta-blockers — they reduce aerobic exercise tolerance at altitude. ACE inhibitors/ARBs and calcium channel blockers are better for “high-altitude” patients.

Type 1 and type 2 diabetes

Altitude changes insulin absorption (cold = slower subcutaneous absorption) and energy demands (increased 30–50% above 4000 m). Type 1: intensive glucose monitoring, adjusted short- and long-acting insulin doses, glucagon reserve, warm insulin storage. Type 2 on metformin: theoretical increased risk of lactic acidosis at altitude, consider a break after diabetology consultation.

Asthma

Exercise-induced asthma and cold are a common combination at altitude. Carry 2× the medication you’d need at home (short-acting beta-agonist, inhaled steroid). Avoid dust (buff!), do peak flow monitoring morning and evening. For severe asthma: HAST before expedition is mandatory.

Cardiac disease

Uncontrolled heart failure, recent myocardial infarction (<6 mo), unstable coronary disease, severe aortic stenosis — contraindications to expeditions >3500 m. Stable coronary disease after revascularization (>6 mo) may be acceptable after cardiology consultation + exercise test + possibly control angiography.

Women — menstrual cycle, contraception

Hormonal contraception and thrombosis risk

Altitude increases deep vein thrombosis (DVT) and pulmonary embolism risk through combination: polycythemia (thicker blood), dehydration, long hours of immobility (flights, lodges). Estrogen contraception adds another 3–4× increased risk. Consider:

• Temporary switch to estrogen-free contraception (progestogen-only — Cerazette, Slinda)
• Hormonal IUD (Mirena) — no systemic estrogen
• Non-hormonal methods during expedition
• Gynecologist consultation minimum 3 months before

Menstrual management on expedition

Menstruation in expedition conditions is not a “delicate matter” — it is a real logistical problem. Options:

• Cycle deferral — continuous use of combined contraception (skip 7-day pause) or progestogen preparations. Consult gynecologist.
• Menstrual cup — doesn’t require running water, used 8–12 h continuously
• Tampons + pad supply — mass to carry (~50 g per expedition day)
• Period underwear (Thinx, Modibodi) — washable, dries in tent

Insurance with helirescue — 7 check points

1. Maximum altitude covered — many policies exclude >4500 m or require surcharge
2. Helicopter evacuation limit — minimum 15,000 EUR (Himalayan evacuation cost 3000–5000 USD + Kathmandu hospitalization)
3. Overseas hospitalization coverage — minimum 50,000 EUR
4. Extension for “high-altitude mountaineering” or “high-altitude trekking”
5. Claim procedure — 24/7 helpline, not e-mail delayed response
6. Mountaineering equipment — does it cover loss/damage (crampons, ice axe, harness can be costly)
7. Trip cancellation conditions — for medical reasons before departure

Recommended providers: World Nomads, Global Rescue, SafetyWing, IMG (Alps). Read the fine print thoroughly.

Frequently asked questions

References

• Luks AM, Swenson ER, Bärtsch P. Acute high-altitude sickness. Eur Respir Rev. 2017;26(143):160096.
• CDC Yellow Book 2024 — Travel Recommendations.
• Wilkes M, MacInnis MJ, Hillebrandt D. Traveling to high altitude with pre-existing diseases. Br J Gen Pract. 2016;66(644):138–139.
• Pollard AJ, Niermeyer S, Barry P, et al. Children at high altitude: international consensus statement. High Alt Med Biol. 2001;2(3):389–403.

Disclaimer: This article is informational and does not replace individual consultation with an expedition or travel medicine physician. The medical plan must be tailored to a specific route, duration, and comorbidities.