Most hangover pills contain ingredients that show some promise in small studies, but no hangover product on the market has been proven to reliably prevent or cure a hangover in humans. Of 82 commercially available hangover products evaluated in a 2021 review published in Addictive Behaviors, not a single one had peer-reviewed human data demonstrating both safety and efficacy. That doesn’t mean every ingredient is useless, but it does mean the bold claims on the packaging run far ahead of the science.
What Hangover Pills Claim to Do
When you drink alcohol, your liver converts it into acetaldehyde, a toxic compound that causes nausea, headache, and general misery. A second enzyme then converts acetaldehyde into harmless acetate. A hangover is largely what happens when acetaldehyde builds up faster than your body can clear it, combined with dehydration, inflammation, and disrupted sleep.
Hangover pills target one or more of these mechanisms. Some aim to speed up acetaldehyde breakdown. Others try to replenish antioxidants your liver burns through while processing alcohol. A few rely on vitamins and electrolytes to address dehydration and nutrient depletion. The products typically instruct you to take two pills before drinking, though some are marketed for the morning after.
Ingredients With Some Evidence
Glutathione (GSH)
Glutathione is your liver’s primary antioxidant, and alcohol consumption depletes it. In a randomized, double-blind, placebo-controlled crossover trial, participants who took glutathione before drinking had significantly lower blood acetaldehyde levels at every time point measured, from 15 minutes to 15 hours after drinking. That’s a meaningful finding because acetaldehyde is one of the direct causes of hangover symptoms. The limitation: lower acetaldehyde in the blood doesn’t automatically translate to feeling great the next morning, and this was a single controlled study.
Dihydromyricetin (DHM)
DHM, extracted from the Japanese raisin tree, is one of the trendiest hangover pill ingredients. Animal studies have shown it reduces signs of alcohol intoxication in rats and eases withdrawal symptoms. But the jump from rat studies to a pill that works for humans is enormous. Robust human trials on DHM and hangovers are still lacking, and 59% of hangover products containing DHM don’t even disclose their dosage on the label.
Red Ginseng
A randomized crossover study in healthy men found that red ginseng drink significantly lowered plasma alcohol levels at 30, 45, and 60 minutes after drinking compared to placebo. Breath alcohol concentration also dropped. Participants reported less severe hangover symptoms. One catch: plasma acetaldehyde actually rose slightly at the two-hour mark, which suggests red ginseng may speed up the first step of alcohol metabolism (converting alcohol to acetaldehyde) without equally boosting the second step (clearing acetaldehyde). The net effect on symptoms was still positive in this study, but the mechanism isn’t cleanly reassuring.
N-Acetylcysteine (NAC)
NAC is a precursor to glutathione, so the theory is straightforward: give your liver more raw material to replenish its antioxidant stores while processing alcohol. Animal studies show NAC can increase glutathione levels during alcohol exposure. In humans, NAC has been shown to boost cysteine and glutathione when the body is under chemical stress, such as during acetaminophen overdose. However, a randomized trial testing NAC specifically for hangover prevention gave participants 600 to 1,800 mg alongside their drinks, and the results were not strong enough to declare it effective. There’s also a regulatory wrinkle: because NAC is registered as a drug by the FDA, it’s technically prohibited as an ingredient in dietary supplements.
Milk Thistle (Silymarin)
Milk thistle is one of the most common ingredients in hangover pills. It has a long history of use for liver support, and a mouse study found that silymarin protected against liver injury from a single large dose of alcohol by reducing fat accumulation, preserving glutathione levels, and lowering inflammation. But most of the research on milk thistle involves chronic alcohol-related liver damage studied over months or years. Whether popping a milk thistle capsule before a night out meaningfully reduces your hangover is an open question with very little human data behind it.
Vitamin B6
One older study found that a high dose of vitamin B6 (1,200 mg of a specific form called pyritinol) reduced the number of hangover symptoms participants reported. But that study never measured symptom severity, only how many symptoms people checked off a list. A more recent analysis looking at dietary vitamin B6 intake and hangover severity found no statistically significant relationship. The evidence here is thin and inconsistent.
The Vitamin Dosing Problem
Many hangover pills pack in vitamins at levels well above what you need. Among the 82 products analyzed in the Addictive Behaviors review, over 62% contained at least one vitamin exceeding the daily recommended intake. About 28% of products listing a vitamin B3 dose exceeded the tolerable upper limit, the threshold above which side effects become more likely. For vitamin B9 (folate), 8% exceeded the upper limit. Meanwhile, many products don’t disclose doses for key ingredients at all, making it impossible to evaluate what you’re actually taking.
High-dose B vitamins can cause flushing, tingling, and gastrointestinal issues. Combining those side effects with a hangover isn’t exactly the relief most people are looking for.
Why the FDA Hasn’t Approved Any of Them
The FDA has sent warning letters to companies selling hangover products that claim to cure, treat, or prevent hangovers. Under federal law, any product making those claims is legally a drug, not a dietary supplement, and must go through the approval process that drugs require. None of these products have done that. The FDA specifically warned that such products could harm consumers, particularly young adults, who might drink more recklessly because they believe a pill will protect them.
This is the core regulatory gap: hangover pills are sold as supplements, which means they don’t need to prove they work before hitting the market. They only need to avoid making explicit drug claims on the label, though many do exactly that on their websites and social media.
What Actually Helps a Hangover
The strategies with the most straightforward evidence are also the least exciting. Drinking water between alcoholic drinks reduces dehydration, one of the major contributors to headache and fatigue. Eating before and during drinking slows alcohol absorption. Electrolyte-rich fluids the morning after help restore what you lost. Sleep gives your liver the time it needs to finish processing everything.
Your liver clears acetaldehyde at a fixed rate. When glutathione stores are depleted, regenerating them takes 8 to 24 hours. No pill has been convincingly shown to compress that timeline in a way that makes a practical difference to how you feel. Some ingredients like glutathione and red ginseng show real biological effects in controlled settings, but “statistically significant reduction in blood acetaldehyde” and “no hangover” are very different outcomes.
The Bottom Line on Hangover Pills
A few ingredients found in hangover pills have genuine biological activity related to alcohol metabolism. Glutathione lowers acetaldehyde levels. Red ginseng appears to speed alcohol clearance. Milk thistle protects liver cells in animal models. But none of these findings have been reliably translated into a product that prevents hangovers in real-world drinking conditions. The dosing is often undisclosed, the vitamin levels are frequently excessive, and the marketing consistently overpromises. You’re spending $1 to $3 per dose on something that, at best, might take the edge off, and at worst, gives you false confidence to drink more than you otherwise would.