Many of us love to discuss the weather with anyone who crosses our path, but can weather be a trigger for those with migraine?

Migraine attacks can be triggered by a combination of genetic and external factors. Genetics, or the inherited tendency to have migraine, can make you more prone to attacks. The external factors can influence when they occur.

People with migraine are particularly sensitive to change. This change in conditions either within the body, (such as dehydration, fluctuating oestrogen), or in the environment (such as the weather) in turn cause changes in the brain that make a migraine attack more likely. Different people experience different levels of sensitivity to known trigger factors. It is often unlikely that any one thing will trigger migraine on its own and it is usually a combination of factors, and weather can be one of these for some people.

Some common triggers include stress, hormone changes, skipping meals or hunger, dehydration, changes in sleep pattern, bright lights, alcohol, heat and weather changes.

Of these, weather change can be difficult for many people with migraine, both at seasonal changes and on a daily basis, more so because it is impossible to control. Stable weather conditions, even with extreme temperatures, can be better tolerated than a changing weather pattern.

The impact of weather on migraine

Weather change can either have a direct or an indirect impact. For example, air pressure may be a direct trigger, causing the attack, whereas warm weather, causing sweating and dehydration may be an indirect trigger.

Types of weather changes that may trigger migraine attacks:

• Temperature changes – In warm weather, more fluid is lost, and this can cause dehydration and trigger an attack. Intense exercise can similarly lead to fluid loss. It will help to increase fluid intake during such times to minimise this potential trigger.
• Changes in barometric / air pressure – Barometric pressure is the pressure of the atmosphere. For example, when a storm is coming, the barometric pressure usually drops. This change is felt by many people with migraine.
• Stormy weather, high humidity and extremely dry weather can also have an impact, particularly when there is a sharp change. Dry weather (including dry, cold weather in the winter) can also increase dehydration, which is another trigger. Warm, humid weather can also disrupt sleep patterns, which can be a trigger for migraine.
• Bright lights and sun glare – Intense sunlight on summer days for example can be a trigger. Migraine causes increased sensitivity to light and exposure to excess light can be a trigger. Sleep might also be affected during long, hot, sunny days and sleep disruption may further increase the chance of an attack.
• Seasonal allergies –allergies do not cause migraine attacks, but migraine is commonly misdiagnosed as a sinus headache, because some symptoms can overlap. It is common for migraine to be associated with forehead and facial pressure over the sinuses, as well as a blocked or runny nose. However, sinus issues may be accompanied by a fever rather than a migraine. Migraine can cause activation of the nerves in the face (referred to as cranial autonomic activation), that can lead to the blocked congested feeling.

Minimising the impact of weather on migraine

If weather changes are a trigger for you, this can be difficult to avoid, and beyond your control, but it can be useful to keep an eye on the weather forecast. Being aware of upcoming extreme pressure, temperature and seasonal changes can help you to prepare.

However, it is not advised that you follow it so closely that your daily activities become dictated by the weather forecast! In cases of extreme sensitivity, a preventive treatment may be needed to reduce the overall sensitivity to such changes, allowing you more freedom to plan your daily activities.

Carry acute medication with you: When you think the weather might increase the risk, it is useful to treat early to shorten and completely stop the migraine attack. Attacks that are treated early will have fewer debilitating symptoms by not becoming fully developed and severe. This will enable a quicker recovery time and allow you to return to your activities.

However, caution is advised in how you use acute medications. If used too frequently, this can lead to medication overuse headache. It’s advised that you keep a record of the medications you’ve taken and discuss these treatments with your GP to reduce the risk of overuse.

Limit other possible triggers: While it is not possible to control the weather, you may choose to limit other possible triggers such as getting adequate sleep and regular meals. This is especially true for people who find that it is the combination of triggers that lead to a migraine attack. Keeping to a consistent schedule is also important, including when on summer/winter holidays and with light and weather changes, as much as possible.

Keeping well hydrated: Drink enough to make up for extra fluid loss on warmer days and physical activities. Consider taking water with you when out to remain well hydrated and to compensate for excessive sweating.

Protecting the eyes: Consider staying indoors during the peak hours of brightness if that is an option. If going out, be prepared by wearing protective sunglasses or a hat to minimise glare and light. The reflection of glare on water outdoors can also be very intense and even short periods of exposure may be difficult.

People experience migraine all over the world and some of their attacks have strong links to the weather. Whilst the impact cannot be eliminated, using these strategies in combination with treatments, should improve tolerance and reduce attacks.