Headache After Smoking Weed? That May be a Pot Hangover

man with weed hangover

Unlike alcohol, which everyone knows can come back to haunt you the morning after a late night out, weed’s supposed to be a substance without severe next-day effects (see our blog on the benefits of cannabis over alcohol).

Even after a night of smoking, weed gives you a high without the dizzying headache, upset stomach, and strong desire to shut out the rest of the world until you’re able to hit the medicine cabinet, replenish your electrolytes, and cook up the best hangover remedy you can think of. Some people even like to hit the pipe for some cannabis-powered relief.

So, what’s the deal with weed hangovers? Why do some people get them, and how can you avoid the unpleasant experience of a headache after smoking weed?

Surprisingly enough, there are a few studies on the effects of pot the morning after. In one study from the nineties, they found no evidence of a so-called weed hangover, but that was nineties weed with THC in the low single digits. Since high-potency strains are now pushing 30 percent THC, and many popular strains are in the high teens to low twenties, the pot that gets you stoned today can be 10 or more times more potent than the pot available just a couple decades ago.

But does the amount you smoke or the potency of the weed matter?

Not really. Marijuana is different from alcohol in that smoking more does not mean the body needs longer to recuperate. Alcohol, on the other hand, is much different. You'll likely want to cancel anything on the calendar tomorrow if you’ve had any more than 5 drinks.

But a night of continuous smoking shouldn’t keep you from tomorrow’s activities, even with high-potency concentrates, because the body should metabolize all THC in just a few hours. So, a night of sleep means the weed you smoked last night shouldn’t affect you in the morning.

You might still be wondering: why is it that some people experience weed hangovers?

The first culprit is withdrawal. We all know that the first thing any budding marijuana enthusiast learns is that pot isn’t supposed to be addictive and isn’t a so-called gateway drug. But that doesn’t mean there aren’t psychological or physical symptoms that can afflict chronic users. From simple cravings to anxiety, irritability, depression, and restlessness, as well as other symptoms like insomnia, headaches, fatigue, and nausea, a weed hangover can take many forms and mean many different things to different people. Certainly, if you consume cannabis constantly throughout the day and then abstain for eight hours each night, you may experience acute withdrawal each morning. And, of course, if you are a heavy daily user and stop cold turkey, your body will start to tell you.

Another common culprit of a marijuana hangover is poor sleep, which can have you feeling restless, tired, and cranky with a nice headache to boot, even after hours of rest. This is because cannabis can interrupt the brain’s ability to enter REM sleep, which is needed to recharge the mind and body for the next day. So, even though your body’s been resting, your mind’s been stoned and unable to recover from the day’s activities. Add a late night, questionable food choices, loud music and other stimulation — maybe even a drink or two — and what was a simple night in with some friends could have turned into a full-blown party, and you’ve got this morning’s headache as a little memento.

But the most common cause of a weed hangover is the same as when you drink alcohol — it’s not the alcohol that gives you the hangover, it’s the dehydration. Remember all those beers and countless trips to the bathroom? Remember not having one glass of water the whole night? That’s what’ll get you the next morning. Alcohol’s a diuretic, and your body has been expelling liquids all night. It’s kind of the same thing with pot, except it’s not the pot that’s drying you out (even though dry mouth and eyes are common side effects of cannabis use). It’s that most people don’t typically consume enough liquids, and it’s easy to skip the water during a marathon blunt session, nevermind the negative effects of smoking blunts. Simply put, if you’re not quenching your thirst with water, Gatorade, or another beverage over the course of a night, you’ll probably wake up the next morning with a headache.

Whatever it is that causes your weed hangover, it’s no fun when you wake up feeling terrible. Some people believe that keeping hydrated is the ticket, while others argue the merits of a solid eight hours of sleep.

So, whether you’ve had headaches, brain fog, dehydration, dry eyes, or general fatigue after a night with Mary Jane, know that a weed hangover is likely the product of your sleep, fluid intake, or some other factor.

And if you’re just starting up after some time off, leave the potent pot brownies until you’ve built up some sort of tolerance or you could end up in one of those multi-day, never-ending pot hangovers where relief can’t seem to come soon enough.

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