Too Much To Drink Last Night? Better Grab Your Shades

It’s the basis for half the romantic comedies ever made and certainly every one that’s set on the Las Vegas Strip: Someone wakes up from a night of heavy drinking only to be greeted by whispered voices that sound like cymbals and blinding bright light even though the room is dim.

Intense sensitivity to light is the key - sometimes exaggerated - component in on-screen hangovers, but anyone who’s had a too-long night on the town knows sunglasses are mandatory in the cold light of morning.

The reason is “photophobia,” a medical condition that can be related to a number of eye and nervous system-related issues, but most commonly manifests alongside migraine headaches and hangovers.

Eye irritation, inflammation and sensitivity to light drives the need to pull on those sunglasses in order to brave a trip down to the buffet for brunch, but the condition is a temporary one, and with a little patience and some common sense, it won’t be around for long.

The warm and fuzzy feelings after all those Long Island Iced Teas comes courtesy of alcohol’s effect as a vasodilator, the drug – yes it’s a drug – widens blood vessels all over the body’s surface, including in the eyes, creating one of the tell-tale signs of a boozy night.

If there’s still a martini glass in hand, it’s a safe bet that morning-after sensitivity to light will fade along with the dry mouth, headache and irrational desire for an Egg McMuffin. But it’s important to know that prolonged light sensitivity can be a symptom of several conditions—from chronic dry eye and conjunctivitis (pink eye) to corneal abrasions (injury to the outermost layer of the eye) and even a life-threatening case of meningitis.

The good news is that for photophobia tied to migraines and hangovers, the treatment is a perfect fit for any sufferer’s nature reaction: Crawl into a dark spot and stay there until it improves. Or at least grab some dark glasses.

The National Institute of Health (NIH) recommends avoiding sunlight, darkening the room, putting on sunglasses or just getting some shuteye. The need to avoid light can be more severe in those with lighter colored eyes, as dark eyes have more pigment to protect against bright lights.

And while the eyes’ light receptors might be a source of temporary agony for a hangover sufferer lying on a Vegas penthouse floor, they’re vital for determining wake-sleep cycles – so much so that even blind people’s pupils contract when faced with a bright light and help set them to natural circadian rhythms.

Satchidananda Panda, a researcher at the Salk Institute, has helped identify a receptor in the neurons connecting the eyes and the brain, called melanopsin, which is responsible for sensing light separately from vision. His team has looked for a decade and finally found a compound that blocks melanopsin, paving the way for medication that could dull the pain of migraines, make daytime sleep easier for swing shift workers and yes, even shade the bright lights of the morning after a night of drinking.