TORONTO -- Valerie South is no fan of summer storms.
While most people just have to worry about getting caught in the rain, for South, the rumbling of thunder can herald the onset of a crippling migraine attack.
South suffers from weather-related headaches, particularly as spring turns to summer. But unlike many who experience similar episodes, she's fortunate enough to have figured out the environmental trigger behind her attacks.
"I'm like a human barometer. I can tell when a storm is coming before I see clouds in the sky," said the 49-year-old.
"Sometimes it can be more mild and sometimes they can be so debilitating that I'm vomiting and I have to go to bed."
South first noticed a link between her attacks and humid, stormy weather some 20 years ago. When over-the-counter medication wasn't helping, she asked other migraine suffers about a potential link to environmental factors and realized there might be something to it.
After speaking to a specialist and developing a plan to cope with the attacks, South began trying to stave off her headaches before they took hold. She discovered she was more susceptible to a weather-related headache if other factors were in play.
"If I'm tired or if I've had alcohol or sometimes chocolate in combination with the storm, the triggers work together to light the fuse that blows the dynamite off in my head," she said.
"I'm always watching the Weather Network and reading the paper and listening to the radio for storms coming in and then I try to be on my best behaviour with my other triggers."
South is now executive director of Headache Network Canada, a charitable organization that aims to educate sufferers and health professionals on all aspects of headache diagnosis and treatment. After years of dealing with her own headaches, South urges others who may be susceptible to similar attacks not to dismiss a potential connection between their pounding heads and the weather.
While the reason for the link between the weather and headaches of varying severity is unclear, doctors now know environmental factors play a big role.
"For a lot of headache sufferers they notice that seasonal change can be a time of worsening headaches..." said Dr. Christine Lay, director of the Centre for Headache at Women's College Hospital in Toronto. "Probably more than 50 per cent of migraine patients have some kind of weather trigger."
Studies have shown a rise in temperature by a few degrees -- no matter what the season -- can trigger headache attacks, she said. Other weather features, including bright sunshine, humidity levels and shifts in barometric pressure are also factors in play.
And while weather changes can have a distinct impact on those who know they suffer from migraine attacks in particular, Lay explained even people who think they might have a simple tension headache ought to consider a link to the environment.
"The majority of migraine patients are undiagnosed," she said, adding weather-triggered migraine attacks are often mischaracterized as sinus headaches or bad tension headaches.
To compound matters, summer activities such as enjoying barbecued meats containing nitrites -- a known headache aggravator -- and a tendency to opt for colourful summer cocktails carrying dyes and artificial sweeteners, can all make a person more vulnerable to a weather-related headache, said Lay.
"It's a combination of the weather change and sometimes what we do in the summer," she said. "The main thing is awareness, rather than discounting it. A lot of people will just say 'Oh, it's just a weather headache.' It's best just not to ignore it, but to really get advice from doctor."
Once people do see their physicians, one of the best ways to deal with weather-related headaches is to figure out just which kind of environmental feature brings on an individual's attack.
"What type of weather-pattern changes trigger off one individual's headaches may not trigger off another individual's headaches. What we suggest is that individuals keep a headache diary," said Dr. Gary Shapero, a Markham, Ont.-based family physician and director of the Shapero Markham Headache and Pain Treatment Centre.
"What they need to do is educate themselves on what the potential triggers are and then try to identify what those triggers are for them."
Once those triggers have been identified, as the weather itself is out of their control, patients are urged to focus on avoiding the headache aggravators they do have power over, Shapero said. That could include ensuring proper sleep and meal patterns are followed.
"People really need to educate themselves," Shapero said. "They need to get to their family physician, and get a proper diagnosis."
-- The Canadian Press