Dry eyes when driving in winter

Winter driving dries the eyes because the heater and defroster push warm, dry air through the car, often straight at your face, while snow glare makes you squint and long stretches of highway cut down on blinking. Aim the vents at your feet and the windshield, take breaks, and pull over before using eye drops. Never put them in while the car is moving.

Why your eyes feel dry driving in winter

Cold outdoor air holds little moisture. When the car’s heater warms that air, it doesn’t add any water, so the air coming out of the vents is warm and very dry. Then the fan pushes it across the cabin. The tear film covering your eye has an oily outer layer that slows evaporation, but dry air moving across its surface for an hour still pulls water off faster than usual. Each blink lays down a fresh coat, so anything that makes you blink less adds to the effect.

Heater vents aimed at your face

• Turn the dashboard vents down or sideways so they aim at your chest or hands, not your eyes.
• Use the floor setting once the cabin is warm. Warm air rises from the footwell without blowing in your face.
• Lower the fan speed after the first few minutes. The temperature stays the same with less air moving.
• If the car has heated seats or a heated steering wheel, they warm you without blowing any air at all.
• Check the passenger’s vents, too. A vent aimed at the person beside you can end up blowing across your face.

Defrost and the windshield

Defrost sends a strong stream of air up the windshield, and much of it rolls back toward the front seats. Visibility comes first: if the glass is fogging or icing, keep the defroster running. Once the windshield is clear, a mixed floor-and-defrost setting usually keeps it clear with less air coming at you. Cracking a rear window for a minute can also help a fogged car clear, though it brings in cold air.

Glare off snow

Fresh snow reflects sunlight back up at you, and the low winter sun can sit right in your line of sight in the morning and late afternoon. People squint against it, and a squint is not a full blink. Keep a pair of sunglasses in the car for winter as well as summer. Polarized lenses cut reflected glare off snow and wet roads, and wraparound frames keep the vent’s airflow off your eyes, too.

Long drives and blinking

Staring at something for a long stretch, whether it’s a screen or a straight, empty highway, tends to mean fewer blinks. On a long winter drive, make a point of blinking fully every so often, especially when the road is quiet. Plan a break every couple of hours. Getting out of the car, walking around and looking at something other than the road gives your eyes a rest from the heater as well.

When to pull over and use eye drops

• Find a safe place to stop: a rest area, a gas station or a parking lot, not the shoulder of a busy road.
• Put the car in park. Never use eye drops while driving or while stopped in traffic.
• Clean your hands. Steering wheels and gas pumps are among the dirtiest things you touch on a trip.
• Tilt your head back against the headrest, pull the lower lid down, and let one drop fall: Apply 1 drop 3 times per day in each eye.
• Keep the tip clear of your eye, your fingers and the car’s interior. Do not touch tip of bottle to any surface to avoid contamination.
• Wait until your vision is completely clear before you drive again.

Don’t leave the bottle in a cold car

A car parked outside on a winter evening falls well below the bottom of the label’s range. Quell’s storage line reads: Store between 15° to 30°C (59° to 86°F). Bring the bottle in with you when you get home, to the office or to a restaurant. If it has been left in a cold car, let it come back to room temperature and look at it before using it. The Do not use line reads: If this product changes color. The guide on eye drops in a hot car covers the summer side of the same problem.

If you’re heading out on a longer trip rather than a daily commute, the guide to eye drops for a winter road trip covers packing and planning.

When it’s more than dry eyes

If your vision blurs or changes while you’re driving, pull over and don’t drive on until it clears. Stop use and ask a doctor if you feel eye pain or changes in your vision, if irritation or redness continues, or if the condition worsens or persists for 72 hours. The guide to eye symptoms that need a doctor goes through the signs the label points to.