As summer tightens its grip across India, rising temperatures bring with them more than just discomfort—they present serious risks to public health. While much of the conversation tends to focus on heatstroke, a lesser-discussed but equally dangerous consequence of extreme heat is dehydration-induced hypotension, or low blood pressure. This condition, often overlooked, can lead to dizziness, fainting, and even life-threatening complications if left unaddressed. With the India Meteorological Department (IMD) forecasting nearly double the average number of heatwave days this year, the need for awareness and preventive action has never been greater.
Extreme heat doesn’t just drain energy—it can worsen chronic health conditions and increase the risk of fatal outcomes. Prolonged exposure to high temperatures has been linked to aggravated cases of cardiovascular and respiratory illnesses, kidney disorders, and complications in people living with diabetes. According to the National Centre for Disease Control (NCDC), India recorded 56 confirmed deaths from heatstroke and over 24,849 suspected cases between March and May last year. A 2023 Lancet study further revealed a 55% rise in heat-related deaths in the country over the past decade. These numbers underline the urgency of tackling heat-related illnesses more holistically, especially as climate patterns continue to shift.
One of the critical but often underestimated effects of dehydration is its impact on blood pressure. Our bodies rely on adequate water and electrolytes to maintain blood volume and ensure efficient circulation. During extreme heat, we lose a substantial amount of fluids through sweating. If not replenished, this leads to reduced blood volume, making it harder for the heart to pump blood effectively. The result is a drop in blood pressure, which can leave individuals feeling weak, light-headed, or nauseous. In more serious cases, dehydration can trigger hypovolemic shock, a condition where vital organs are starved of oxygen-rich blood—a life-threatening emergency.
Certain populations are more vulnerable to these effects. Older adults, for instance, may have a diminished sense of thirst, making them less likely to drink enough water. Outdoor workers such as farmers, construction workers, and street vendors are constantly exposed to high temperatures and may not have consistent access to fluids or rest. Individuals with chronic conditions like diabetes, high blood pressure, or kidney disease are also at greater risk, especially if they’re on medications such as diuretics that can further deplete fluids. For these groups, the combination of intense heat and dehydration can be particularly dangerous.
Fortunately, many of the risks associated with dehydration and low blood pressure can be prevented with simple lifestyle measures. Staying hydrated is the most important step—drinking at least 8 to 10 glasses of water a day, and more during particularly hot days. Fluids like coconut water or oral rehydration solutions (ORS) are especially helpful in replacing lost electrolytes. It’s also advisable to avoid being outdoors between 12 PM and 4 PM, when the sun’s intensity peaks. Wearing light clothing, staying in the shade, and using fans or cooling methods can help reduce body temperature. Family members should also check in on the elderly, children, and those with underlying health conditions to ensure they are drinking enough fluids and not showing signs of dehydration.