A major heat wave is expected to hit much of the eastern United States this week. And millions of people across the country are taking medications that may make them more susceptible to heat-related illnesses.
Taking certain drugs — including some used to treat mental health conditions, high blood pressure and allergies — can make it even more difficult to stay hydrated or efficiently cool your body when it’s hot outside. Here’s what to know, and how to stay safe during scorching temperatures.
Medications that may raise risk
Diuretics, which doctors prescribe to manage heart failure, kidney disease or high blood pressure, help your body reduce fluid through frequent urination. But they can also cause dehydration or lead to an imbalance of electrolytes such as potassium or salt, which make it harder for the body to regulate its temperature, said Allison Hill, the director of practice implementation and professional affairs at the American Pharmacists Association.
This can be especially dangerous in extreme heat, which also leads to dehydration. Experts said that makes it even more crucial for people on diuretics, also called water pills, to replenish with water and electrolytes and to pay attention to signs of dehydration and overheating.
Angiotensin converting enzyme inhibitors, or ACE inhibitors, which are commonly prescribed to treat high blood pressure, can increase the risk of fainting and falling, particularly in extreme heat, said Dr. Michael Redlener, the medical director of the emergency department at Mount Sinai West. They also suppress the feeling of thirst, making it harder to tell when you need to drink more water.
Beta blockers, another type of blood pressure medication, can also increase the risk of fainting and falls and make it harder to sweat, which makes it more difficult for your body to keep cool.
Blood pressure drugs known as calcium channel blockers can cause electrolyte imbalances, Dr. Redlener said, making it difficult to regulate body temperature.
Certain antipsychotic medications such as haloperidol, olanzapine and risperidone affect your ability to sweat, too, Dr. Redlener said. “Your body temperature has a higher likelihood of getting hotter when you’re on those medications,” he said.
Some antidepressants can increase sweating and repress thirst, which — much like frequent urination — can lead to dehydration during heat waves. And thyroid hormone replacement medications also can raise body temperature, impair temperature regulation and cause excessive sweating.
Stimulants, such as amphetamines and other drugs used to treat attention deficit hyperactivity disorder, may increase the risk of heat-related illnesses by interacting with the central nervous system and brain to raise body temperature, said Dr. Mahesh Polavarapu, the medical director of emergency medicine at NewYork-Presbyterian Westchester.
Some over-the-counter antihistamines such as diphenhydramine (Benadryl), promethazine and doxylamine (Unisom) also make you sweat less and can impair temperature regulation, Dr. Polavarapu added.
How to Stay Safe in Extreme Heat
If you are at higher risk of heat illness because of your medications, there are precautions you can take to keep cool.
First, know the signs of heat-related illness: Symptoms of heat exhaustion include heavy sweating; cold, pale or clammy skin; headaches; nausea; or vomiting. People experiencing heat-related illness can also experience muscle cramps and feel dizzy or fatigued.
In more serious cases, overheating can lead to heat stroke, which happens when the body temperature hits 103 degrees Fahrenheit or higher. Your skin may look different — it may be red, hot, dry or damp — if you have heat stroke, according to the Centers for Disease Control and Prevention. Heat stroke may also cause confusion or a persistent headache, and may even lead someone to lose consciousness. If you or someone you know exhibits these symptoms, seek emergency medical care immediately, Dr. Polavarapu said.
If possible, Dr. Redlener said, stay inside in an air-conditioned environment. If you don’t have access to an air-conditioner at home, visit a cooling center, such as a library.
If being outside is unavoidable, Dr. Hill said to drink plenty of water and stay in the shade as much as possible. You should also try to keep your electrolytes replenished, which you can do with sports drinks, other electrolyte-infused beverages, fruits and leafy greens. Dr. Hill recommend drinking 8 ounces of water every 15 to 20 minutes if you’re outside — or inside with no air conditioning — during a heat wave.
You can also fend off heat by wearing loosefitting clothing with lighter colors that reflect the sun, Dr. Polavarapu said. If you can, try to limit your time outside to the early morning or late evening, which are the coolest parts of the day.
