High Blood Pressure In Summer
How heat, dehydration, and blood-pressure medications can affect your health
By Rodrico Gordon, DNP-C, AGPCNP-BC, NE-BC
Key takeaway: Hot weather can place extra strain on the cardiovascular system. Adults living with hypertension pressure should pay close attention to hydration, symptoms, home blood-pressure readings, and medication safety during periods of extreme heat.
How summer heat affects high blood pressure
During hot weather, the body works harder to stay cool. For people managing high blood pressure or hypertension, this seasonal change deserves extra attention. Blood vessels near the skin widen, the heart pumps more blood toward the skin, and sweating increases fluid loss. These normal responses can change blood pressure and make the heart work harder—especially when heat and humidity are severe.
Dehydration reduces the amount of circulating fluid in the body. Some people may experience a drop in blood pressure, dizziness, weakness, or fainting. At the same time, heat stress and dehydration can increase heart rate and cardiovascular demand. The effect is not identical for everyone, which is why symptoms and home readings should be interpreted in context.
Blood-pressure medications, dehydration, and heat
Some commonly used medications can affect how the body responds to heat. Diuretics, sometimes called “water pills,” increase fluid loss through urination. Other cardiovascular medications may influence blood-vessel dilation, sweating, heart rate, kidney function, or the body’s ability to maintain fluid and electrolyte balance.
A 2024 peer-reviewed systematic review and meta-analysis found that certain prescription and over-the-counter medications can alter core-temperature responses during heat stress. However, the evidence varied by medication class and was limited for several drugs. Medication decisions therefore need to be individualized rather than based on a general list.
Medication safety: Do not stop, skip, reduce, or change a blood-pressure medication on your own because of hot weather. Contact your healthcare provider if you develop new symptoms, unusually low or high readings, reduced urination, vomiting, diarrhea, or difficulty staying hydrated.
Warning signs to take seriously
Heat exposure, dehydration, or an abnormal blood-pressure response may cause:
· Dizziness, lightheadedness, or fainting
· Unusual weakness or severe fatigue
· Headache, nausea, or muscle cramps
· Rapid heartbeat or palpitations
· Confusion, poor coordination, or unusual behavior
· Chest discomfort or shortness of breath
Confusion, loss of consciousness, seizure, very hot skin, or an inability to cool down may signal heat stroke and requires emergency care. Call 911 for chest pain, severe shortness of breath, fainting, stroke symptoms, or other life-threatening symptoms.
Summer blood-pressure management and heat-safety tips
1. Check your blood pressure correctly
Rest quietly for at least five minutes before checking. Sit with your back supported, feet flat on the floor, legs uncrossed, and the cuffed arm supported at heart level. Avoid exercise, caffeine, and smoking for approximately 30 minutes beforehand. When possible, take two readings about one minute apart and record both.
2. Hydrate thoughtfully
Drink fluids regularly instead of waiting until you feel very thirsty. Water is appropriate for many people, but hydration needs differ. If you have heart failure, kidney disease, liver disease, or have been instructed to limit fluids or sodium, follow your clinician’s individualized plan.
3. Reduce peak heat exposure
Use air conditioning when available, seek a cooling center if needed, wear lightweight clothing, and schedule outdoor activity for cooler parts of the day. Take more frequent breaks and avoid strenuous activity when the heat index is high.
4. Protect and store medications properly
Keep medications out of direct sunlight and never leave them in a hot car. Heat can damage some medications and medical supplies. Review storage instructions on the label or ask a pharmacist when you are uncertain.
5. Know your usual range
One unusual reading does not always mean there is an emergency, but a pattern matters. Record the date, time, blood-pressure reading, pulse, symptoms, recent activity, fluid intake, and whether medications were taken. This information can help your healthcare provider make safer decisions.
When to seek care for high or low blood pressure
Contact your healthcare provider when readings are repeatedly outside your usual or recommended range, when dizziness or weakness persists, or when you are unsure whether a medication or fluid restriction changes your heat-safety plan.
A blood-pressure reading higher than 180/120 mm Hg should be repeated after at least one minute. If it remains that high and you have chest pain, shortness of breath, weakness, numbness, vision changes, difficulty speaking, or other concerning symptoms, call 911. If there are no symptoms, contact a healthcare professional promptly for instructions.
Personalized care can make summer safer
High blood pressure often causes no obvious symptoms, but hot weather can complicate hypertension management. A medication review, home-monitoring plan, and individualized hydration guidance can help reduce risk while keeping blood pressure controlled.
Gordon Wellness Service NP in Adult Health provides hypertension management in Queens and Brooklyn, including adult primary care, blood-pressure checks, chronic disease management, medication review, preventive care, and telehealth services for adults in New York.
Schedule an appointment: Visit www.rose-hall-wellness.com or call (516) 564-3496. Queens: 190-19 Linden Blvd., Suite 1A, Jamaica, NY 11412. Brooklyn: 1786 Flatbush Avenue, Brooklyn, NY 11210; (929) 438-6996 or (516) 564-3496.
References
Hospers, L., Dillon, G. A., McLachlan, A. J., Alexander, L. M., Kenney, W. L., Capon, A., Ebi, K. L., Ashworth, E., Jay, O., & Mavros, Y. (2024). The effect of prescription and over-the-counter medications on core temperature in adults during heat stress: A systematic review and meta-analysis. EClinicalMedicine, 77, 102886. https://doi.org/10.1016/j.eclinm.2024.102886
Desai, Y., Khraishah, H., & Alahmad, B. (2023). Heat and the heart. Yale Journal of Biology and Medicine, 96(2), 197–203. https://doi.org/10.59249/HGAL4894
Medical disclaimer
This article is intended for general educational purposes only and does not replace individualized medical advice, diagnosis, or treatment. Do not change prescribed medication, fluid intake, or sodium intake without consulting a qualified healthcare professional. Call 911 for a medical emergency.
