Every year, thousands of visitors arrive in Cusco eager to explore one of the world’s most spectacular destinations. Most travelers are aware of altitude sickness and take steps to prevent it. Lake and Louise altitude mountain sickness score is a tool widely used to determine the severity of altitude sickness. Far fewer realize that high altitude can also affect blood pressure, particularly among people who already live with hypertension.
As a physician working in the Peruvian Andes, I have seen many travelers with well-controlled blood pressure enjoy their visit without difficulty. However, I have also encountered individuals who were surprised to discover that their blood pressure rose significantly upon arrival at altitude, and some of them developed altitude sickness simultaneously. Understanding these changes before traveling can help visitors prepare appropriately and enjoy their trip.
Cusco sits approximately at 3,400 meters (11,150 feet) above sea level. At this elevation, oxygen levels are lower than at sea level, triggering a series of physiological adaptations. The body activates the sympathetic nervous system by increasing heart rate, and blood vessels constrict in certain vascular networks. As a result, blood pressure often rises.
Studies have consistently shown that acute exposure to altitude increases blood pressure in both healthy individuals and people with hypertension. In one study conducted at an altitude similar to Cusco, participants with mild hypertension experienced an average increase of approximately 11 mmHg in their 24-hour systolic blood pressure after ascent. However, it’s important to recognize that individual responses varied considerably. Some participants experienced only modest changes, while others showed increases exceeding 25 mmHg, with daytime average systolic pressures surpassing 160 mmHg. These findings reflect what many clinicians observe in practice: altitude affects blood pressure differently from one person to another (Bilo, G. et al., 1979).
For many travelers, the greatest cardiovascular challenge is not Cusco itself but excursions to even higher elevations. Popular destinations in the Andes frequently exceed 5,000 meters, where lower oxygen levels and physical exertion place additional demands on the cardiovascular system. Research from the HIGHCARE-HIMALAYA study demonstrated that blood pressure increased after ascent to 3,400 meters and rose further at 5,400 meters, remaining elevated even after nearly two weeks of acclimatization (Bilo, G., 2019). These findings suggest that cardiovascular stress may continue to increase as travelers venture to progressively higher elevations.
Several additional factors may influence blood pressure at altitude. Many visitors consume coca tea or chew coca leaves to help alleviate altitude-related symptoms. Nevertheless, coca leaves contain alkaloids with mild stimulant properties which have been shown to produce measurable cardiovascular effects, including increases in heart rate and blood pressure (WHO, 2025). While these effects are generally modest in healthy individuals, there is limited research evaluating their impact among travelers with pre-existing hypertension.
Medication use is another often overlooked factor. Travelers frequently assume that medications used for altitude acclimatization are universally benign. In reality, individuals taking stimulant medications, including some prescribed for ADHD, may experience additional cardiovascular stress at altitude (Pitman JT, 2012). In my clinical practice, I have encountered travelers whose blood pressure rose substantially when stimulant medications, high-altitude exposure, and acclimatization therapies coincided. Although the precise contribution of each factor is often difficult to determine, these cases underscore the importance of reviewing medications before traveling.
Fortunately, for most people with well-controlled hypertension, high altitude is not a reason to avoid visiting Cusco. A few simple precautions that any travel doctor will suggest can help you to reduce risk:
Check your blood pressure before departure.
Bring an adequate supply of all prescribed medications.
Continue antihypertensive treatment as directed.
Monitor your blood pressure during travel if feasible.
Use a portable tensiometer if possible, during travel.
Ascend gradually when possible.
Seek medical attention if you experience severe headaches, chest pain, neurological symptoms, or markedly elevated blood pressure readings.
Discuss travel plans with your physician if your blood pressure is poorly controlled or if you take multiple medications that may affect cardiovascular function.
Travelers planning a visit to Cusco often focus on oxygen saturation and altitude sickness. Yet for millions of people living with hypertension, another important number deserves attention: blood pressure. The available evidence suggests that blood pressure commonly rises after ascent to high altitude, although serious complications remain uncommon in individuals with mild to moderate, well-controlled hypertension. Because responses vary substantially from person to person, awareness and preparation are key.
With appropriate planning, most travelers with hypertension can safely experience Cusco’s extraordinary history, culture, and landscapes while minimizing avoidable cardiovascular risks.
Autor: Romina Rios M.D.
