The experience of brain fog is in the name itself: it’s like a haze that drifts over your mind, affecting your ability to think, reason, remember, or concentrate.
According to the Merriam-Webster dictionary, brain fog is “a usually temporary state of diminished mental capacity marked by inability to concentrate or to think or reason clearly.”
With cessation of marijuana, you might feel as though your brain just doesn’t seem to work as fast as you want it to. Some people describe feeling as through their brain and body are out of sync with each other. Other people experience more difficulty with concentrating on tasks, or difficulty with memory. As with other withdrawal symptoms, the cognitive difficulties you may encounter will be unique to you, and represent your brain recalibrating its neural circuity from extended marijuana use.
Again, there’s biology to explain why you’re feeling slow. More importantly, there’s also biology to explain why brain fog is not permanent. Acute marijuana intoxication is akin to putting your brain through a mental meat-grinder. In scientific studies, that translates to measurable impairments in verbal memory, attention, and basic motor coordination (Crean, J Addict Med, 2011; Broyd, Biol Psychiatry, 2016).
There is further evidence to suggest that acute intoxication interferes with higher-level brain functions like planning, organizing, problem solving, decision-making and risk-taking, which are collectively referred to as executive functions.
Impairments in executive function will continue in the hours to days after stopping marijuana use and may last up to a month (Crean, J Addict Med, 2011). You will notice that some things, like your coordination, attention span, and short-term memory recover faster than others. That’s normal. Depending on how long you’ve smoked for, and how much you smoke, it may take longer for your brain to recover. By approximately 1 month, however, the differences in executive function in former heavy users and non-users approaches zero (Pope Jr, J Clin Pharmacol, 2002).
To summarize, the ultimate cure for brain fog is time. In the meantime, though you can optimize your actions and routines for your daily functioning. Eating healthy, exercising, and maximizing your sleep can help boost your brain processing while it’s on the mend from chronic marijuana use. If you’re having difficulty remembering tasks or items, make reminders for yourself with lists or alarms on your smartphone or devices. Be patient with yourself—we believe in you.
Would you mind answering a few questions (anonymously)?
Currently, little data exists on brain fog and marijuana use. Weedless.org is collaborating with researchers to explore this topic and others. We have created a short, anonymous survey which we will use to focus our future research efforts.
Your participation is appreciated and completely anonymous. You may skip any questions that make you feel uncomfortable and you are free to withdraw at any time.
Weedless.org is a free, web-based resource and community created by a team of healthcare professionals and researchers. We distill the facts about marijuana use and its effects into practical guidance for interested persons or for those who are thinking about or struggling to quit weed. Finding reliable, easy to understand information about marijuana should never be a struggle—that is why our core mission is to provide the most up to date information about marijuana use, abuse, addiction, and withdrawal. While we seek to empower individuals to have control over their use, we are not "anti-weed" and we support efforts to legalize adult marijuana use and study.