Why summer heat can trigger migraines
Rising temperatures can mean rising pain for many people, as summer heat can often trigger the onset of migraine headaches. As temperatures climb, so do migraine episodes, with heat, humidity and dehydration being some of the most common reasons for the start of a migraine during the summer months.
Some neurologists say summer is often one of the worst seasons for patients with migraine. Even brief exposure to high temperatures or skipping hydration on a hot day can set off a debilitating attack that may last hours or days.
Migraine is a chronic neurologic disorder that results from a complex interplay of genetic and environmental factors.
“People who have a migraine disorder have brain changes that cause repeated episodes of headache and sometimes other types of pain (like in the face or neck), light sensitivity, sound sensitivity, nausea, and sometimes vomiting,” explains Dr. Andrea Synowiec, board-certified neurologist and assistant director of Allegheny Health Network’s (AHN’s) Headache Center. “Even between attacks, people with migraine disorders can have changes in some kinds of brain function.”
Migraine headaches are often one-sided and throbbing, but they can also be steady or involve the whole head, so it’s a good idea to see a physician at least once to talk through the symptoms and make sure you know the type of headache you are having.
There are many potential migraine triggers, and the best strategy is to try to avoid them when possible, to reduce the number of life-disrupting episodes of migraine.
“However, weather can be frustrating because it is not something we can control,” says Synowiec. “While the exact mechanism behind why certain types of weather can trigger migraine attacks is not understood, there are some leading theories. Most likely, heat and humidity trigger migraines through increased sweating and fluid loss, causing changes in electrolyte balance and stress on the body as it tries to maintain homeostasis.”
The heat can also exacerbate other migraine triggers like poor sleep, which can create a “perfect storm” of migraine triggers building on one another.
In addition to heat and humidity, any big change in weather can act as a migraine trigger because of the disruption to the body’s internal stability (homeostasis).
“Large fluctuations in barometric pressure – whether rising or falling – have been noted to increase susceptibility to migraine attacks in some patients,” Synowiec said. “Sudden changes in temperature can also affect the diameter of blood vessels and trigger the release of stress hormones, which can trigger migraine for some people.”
Hydration is a crucial ingredient in preventing migraine onset. “
This probably happens through several mechanisms,” Dr. Synowiec explains. “When we don’t take in enough water, we can have a decrease in the volume of blood circulating throughout the body including the brain. Since the brain is very sensitive to changes in blood flow, a reduction can trigger a cascade of events that can lead to migraine.”
Another factor is that the electrolyte imbalance that comes from excessive sweating can cause changes in the body’s amount of sodium, potassium, and magnesium. “These are crucial for proper nerve function, and disrupting their normal excitability patterns can contribute to migraine symptoms.”
Maintaining a good fluid balance is important.
“Be sure to take in enough water to stay hydrated and replace electrolytes that can be lost in sweating,” says Synowiec. “This can be done with sports drinks, electrolyte tablets, or even foods that replenish key electrolytes like sodium, potassium, and magnesium. Regulating caffeine and alcohol intake is important, since both can contribute to dehydration and can also independently act as migraine triggers.”
She also recommends avoiding peak heat when possible by limiting outdoor activities during the hottest parts of the day.
“You can also avoid other controllable migraine triggers – keep sleep regular, manage stressors, and choose fresh, healthy foods over highly processed options, aged meats (like hotdogs – best part of a cookout but a big migraine trigger for many) and aged cheeses during times of extreme heat.”
Charting migraine symptoms, potential trigger exposures and use of any medications to treat the attacks is helpful if you do need to see a doctor for headaches.
“This information will help your health care provider make the right decision about any testing or treatment needed for headaches,” said Synowiec. “There are lots of ways to do this including paper calendars and smart phone apps that can help keep this data together for you to review with your doctor.”