Medically reviewed by Femi Aremu, PharmD
Written by Jessica Caporuscio, Pharm.D.
The legalization of weed in multiple states is prompting more and more people to become interested in its after effects, including whether or not it can lead to a “hangover.”
Researchers have studied the health effects of marijuana, but they currently know very little about “weed hangovers.”
In this article, learn more about potential weed hangovers, including some symptoms and possible cures.
Can using marijuana lead to a hangover?
Medical professionals do not yet know if weed causes a hangover, and only a few studies describe weed hangovers. Some suggest that using weed can lead to hangover effects, while others indicate the opposite.
The reported effects of weed use vary widely between studies, and researchers do not know if the participants in these studies used other substances alongside weed. It is also unclear whether or not age or sex can influence the “hangover” effects of using marijuana.
Studies that say it can
In 1985, researchers conducted a study examining the after effects of smoking marijuana. The study only included 13 males, but it showed that a hangover effect from using weed might exist.
Other research teams continued to study whether or not weed hangovers might exist, as well as what people can expect the morning after using the drug.
One study showed that smoking weed can lead to daytime fatigue the following day. Another study suggested that smoking weed can have significant after effects, such as irritability and feeling miserable.
More recent research analyzed the results of 19 different studies into marijuana use and its negative effects. The researchers found that marijuana had a “medium sized association” with certain negative effects.
Studies that say it cannot
One study showed that participants who smoked marijuana in a controlled setting experienced effects for a few hours, with levels falling after 3.5 hours. The investigators did not notice any effects of marijuana the day after the person used it.
The National Institute on Drug Abuse explain that the noticeable effects of smoking marijuana last around 1–3 hours. These effects may last longer if the person ingests marijuana in the form of edibles.
It is unclear whether or not frequent users have a different experience than infrequent users.
Each of these studies had a different design and used different amounts of the drug. If the negative effects of marijuana use are dose-dependent, this might also partially explain the differing conclusions of each study.
Researchers from the New York Psychiatric Institute studied the dose-dependent effects of marijuana. They noticed a dose-dependent effect on increased heart rate and decreased marijuana cravings in people who smoked weed.
During this study, the effects on attention, psychomotor function, and recall tasks were not dose-dependent. It is unclear whether or not this is the case when a person takes edible preparations.
Now that most of the United States and many countries around the world have legalized marijuana, researchers have the opportunity to conduct further studies into the potential of weed hangovers.
The effects of marijuana use may linger for hours. If a person smokes or vaporizes the drug, these effects may last between 1 and 3.5 hours.
Ingesting marijuana in the form of edibles causes longer-lasting effects than inhaling it. A person who takes edibles may experience effects for up to 8 hours. These effects may last even longer depending on the amount of marijuana the person used. So, if a person takes an edible at night, they may still feel the drug’s effects the next morning.
Some potential effects of marijuana include:
- dry mouth
- increased sense of happiness
- increased heart rate
- breathing problems
Potential ‘weed hangover’ effects
A study in the journal Pain explored people’s perspectives on using marijuana for pain relief. Some reported weed hangovers that caused a foggy feeling in the morning. Some also felt a lack of alertness the day after using marijuana.
Some other potential effects of a weed hangover include:
- dry mouth
- dry eyes
- mild nausea
However, it is important to remember that some people use marijuana and alcohol at the same time. In these situations, it may be difficult to know which substance is responsible for the effects.
People who feel fatigued the morning after using marijuana may need to sleep for a little longer to start feeling better. Although caffeine may help promote alertness, the body may still need extra sleep.
To resolve the feeling of a dry mouth, it is important to stay hydrated, especially if a person combined marijuana with alcohol.
Anyone experiencing nausea should try to eat small, frequent portions the next day.
The following remedies may also help with the effects of a weed hangover:
- Take a hot shower: A hot shower can leave a person feeling refreshed and help with any feelings of lethargy and fatigue.
- Eat a healthful meal: A nutritional meal can provide hangover relief.
- Use a pain reliever: These can help with headaches.
- Stay hydrated: Marijuana can lead to dehydration, so drinking plenty of water is important.
- Avoid caffeine: Although caffeine can help with sleepiness, it can also worsen dehydration, so be sure to drink plenty of other fluids.
Effects such as increased heart rate, confusion, dizziness, and disorientation will disappear with time. If they do not, a person should speak with a doctor as soon as possible.
Like alcohol-induced hangovers, the best way to prevent a weed hangover is to use the drug in moderation. No other prevention methods have any scientific validity yet.
The Canadian Nurses Association suggest that a person can reduce the health risks of marijuana use by:
- minimizing how often they use the drug
- stopping using it when it becomes hard to control cravings
- avoiding using it with tobacco, alcohol, and other substances
- avoiding large doses
Weed hangovers vs. alcohol hangovers
People who drink a lot of alcohol may experience a hangover. Some symptoms of an alcohol hangover include:
- memory problems
- visual-spatial difficulties
- concentration difficulties
- sleep disturbances
Some research suggests that ethanol’s main byproduct, acetaldehyde — in combination with several other of alcohol’s main components — is what causes hangovers. These substances cause hormonal and immune system issues.
Whether or not a person experiences a hangover will depend on how much alcohol they drank and how well they tolerate it. It may also depend on how much time has passed between drinks, and whether or not the person consumed any food before drinking. Dehydration can also contribute to a hangover.
However, there is limited scientific evidence as to the exact symptoms of a hangover. This is the case for both weed and alcohol hangovers.
Researchers and medical professionals still do not know if weed can cause a hangover. With the legalization of marijuana in many different countries, states, and provinces around the world, more people have access to it than ever before.
To determine whether or not using weed causes a hangover, researchers must continue to explore this area.
However, each person may have a different experience of and tolerance to marijuana, so the results of scientific studies may always differ.
Building up more evidence to describe the weed hangover will allow doctors to better counsel people experiencing effects the day after using weed.