Nothing gives a stoner away faster than blood-red eyeballs. A few good bong rips can turn your eyes into a bright patchwork of blood vessels that only a blind person could ignore.
But why does it happen? Is there anything we stoners can do to keep it from happening, or make it go away? Are there believable excuses for your red-eye? Could you just stay home today?
The biology behind red eyes is actually very simple. The THC in weed – the chemical that gets users high – causes a drop in blood pressure that increases blood flow throughout the body and allows blood vessels to expand.
THC expands blood vessels
That includes the blood vessels in your eyeballs. They expand and fill with blood, giving your eyes a veiny, bloodshot look. These blood vessels don’t go anywhere when you’re not stoned, they’re just a lot harder to see.
Contrary to popular belief, red-eye usually isn’t caused by exposure to marijuana smoke. You can get it whether you toke the drug, eat it, or ingest it some other way. Some users do suffer allergies or sensitivities that cause rhinitis, the excess production of tears and mucus. But THC is the real culprit in most cases, even if the smoke doesn’t help.
Not everyone reacts to THC the same, though, and that’s true in a variety of ways. Just as no two highs are exactly the same, different people react to the drug differently. A lot of people get red-eye, but other users don’t.
Genetics play a role
Why? Genes can play a big role, for one thing. Some lucky folks are just predisposed to clear eyes, even when they’re high. Others can’t help but look like they’re suffering from pink eye every time they get near a bong.
Tolerance also plays a part in how bad the effect is. If you’ve used a lot of pot for a long time, your eyes are less likely to give you away.
What’s more, some pot strains produce more red-eye than others. This can result not only from THC but from its interplay with other chemicals in weed. Marijuana is packed with these cannabinoids, and their interactions shape the drug’s effects.
The bottom line is, if you use dope, you might get red-eye. Then again, you might not. There’s not a lot you can do to determine which it will be. But there are a few things you can do to deal with the problem once it arises.
Visine constricts blood vessels in the eye
Visine is usually the brand of choice for panicked stoners. It’s easy to find at any 24-hour drug store, it’s cheap, and holding it isn’t probable cause. Visine is a decongestant, and it works by constricting the blood vessels in the eye, much as it would if you had a cold.
But don’t overdo it. Using Visine or any decongestant on your eyes for more than two or three days can make the problem worse. And Visine can trigger allergies or interact badly with certain other medications.
Alternatively, use artificial tears. Though these don’t constrict the blood vessels, they will reduce irritation and dryness. And they’re safer and less irritating than Visine.
Or, what the hell, just roll with it. Go to the bank and make a suspiciously large withdrawal or deposit. Flag down a cop for directions. Visit your local dispensary and ask if they know where you can score some PCP. You know, have fun with it.
Because once that dreaded red-eye appears, you’re going to have a heck of a time convincing anyone you’re sober.