How Alcohol and Drugs Wreak Havoc on Your Brain’s Memory

Image by

For centuries, substance abuse has been associated with health issues, drunkenness, and memory loss. In fact, ancient cultures alternate between considering alcohol and drugs a blessing and a curse. For some, substances are an important way to heighten or enable spiritual experiences. And in other settings, substances cause various health problems.

One of the most classic examples of substances causing memory problems is alcohol. Drunks are described throughout history as having trouble remembering what has happened from one day to the next. Similarly, centuries of medical texts praise the blessings of opium while warning of its dangers. Cravings for the drug were well-known, even though opium was the best available painkiller for centuries.

Nowadays, science has answers to why memory loss occurs. While we’ll discuss this further in this article, various drugs cause brain damage, while others interfere with the formation of memories. Because memory loss is devastating and sometimes irreversible, it’s important to understand how various substances can wreak havoc on our brains.

Image by Wolfgang Eckert from Pixabay

The Science of Memory

Over the last twenty years or so, scientists have gained important insights into how drugs and alcohol alter our brains and their chemicals. There are many different effects that drugs can have on the human body, but their ability to rewire our brains are our focus here.

Our brains form memories through the activation, and reactivation, of various neurons. Brain chemicals, like dopamine and serotonin, help our neurons to fire in certain ways during our lives. For instance, a child will often feel positive emotions when visiting their grandparents. Similarly, learning something we find interesting will encourage us to remember it. When we retrieve memories, our neurons fire differently to recall the information.

Memories are formed in several different parts of the brain. For instance, the hippocampus helps us remember what happened at the party last night, and the neocortex extends that memory so we can recall it in a month’s time. Either way, the amygdala connects memories with emotions. Finally, the basal ganglia, cerebellum, and prefrontal cortex let us work with memories and perform routine tasks.

Different environmental factors can affect how drugs and alcohol affect us and our memories. The most common example of this is when people drink alcohol when tired: often, it doesn’t take as much alcohol to get drunk as it would when the same person is well-rested. 

Image by Michal Jarmoluk from Pixabay

The Effects of Alcohol on Memory

When you drink alcohol, it disrupts the neurotransmitters in the memory centers of your brain. Depending on the amount of alcohol and the individual, there can be several immediate effects. Initially, most of us feel relaxed, and we lose our inhibitions. At the same time, it becomes more difficult for our brains to form memories. Specifically, our brain is less able to turn episodic memory from the hippocampus into longer-storage memories in the prefrontal cortex and other parts of the brain. 

When alcohol intake gets high enough, heavy drinkers often experience blackouts and memory lapses. These are episodes where someone doesn’t remember what happened while they were impaired. A classic example of this is when, after a party, someone wakes up in an unfamiliar location and can’t figure out how they got there. Partial memory loss and fragmented memories are also possible, where someone remembers a snapshot of incidents but not the whole episode.

Similarly, drinkers may experience problems with working memory. In these situations, it can be difficult to remember something from one moment to another. That person might lose track of what they were saying a minute ago or be unable to solve basic problems. Similarly, reaction time slows, leading to impairment in everyday functioning. This is one reason why it’s illegal to drink and drive.

Long-term decline

While most of the effects we’ve mentioned already primarily affect short-term memories, long-term damage is also possible. Families of people who drink often watch their loved ones become forgetful, lose their balance even when sober, and even develop tremors.

There are several reasons why long-term alcohol abuse and alcoholism can have these results. Some of them involve poor nutrition, neurological problems, and overall declining health. However, the most important threat to memory in alcoholics is Wernicke-Korsakoff syndrome.

What is Wernicke-Korsakoff Syndrome?

It’s a combination of two conditions, Wernicke’s disease, and Korsakoff Psychosis. Both are the result of thiamine (vitamin B-1) deficiency which can develop after years of heavy drinking.

Wernicke’s disease typically develops first. Symptoms include confusion, muscle tremors or other problems with motor control, lethargy, trouble controlling body temperature and blood pressure, loss of consciousness, and vision problems. These challenges can be very upsetting to the patient, but they are often even more alarming to the people who must watch the person they love deteriorate. At the same time, some problems like balance and vision deficits can be dangerous to the patient because they increase the chances of accidents and falls.

Korsakoff’s Psychosis is more severe. Besides the symptoms of Wernicke’s disease, patients develop severe memory problems. Specifically, they can slowly lose the ability to form memories (amnesia) or to recall existing ones. They might have false memories that cause them to “make stuff up” or experience hallucinations. Also, it’ll become more difficult to do everyday tasks or to stop making repetitive motions. Patients may also struggle to make decisions and may become apathetic about life.

All these symptoms range from mild to severe, leading to impairments that can rob someone of their quality of life. Eventually, they can become dependent on others for everyday tasks.

Fortunately, you can sometimes treat Wernicke-Korsakoff syndrome if it’s caught early enough. Specifically, the symptoms of Wernicke’s disease are treatable with Thiamine injections and supplementation. Typically, it’s a long way to recovery because vitamin deficiencies can take a while to reverse. While patients may not recover to their baseline, there’s a chance that supplementation will stop the progression of the disease. Psychosis is irreversible, though supplements may stop the condition from worsening.

In either case, symptom management may be available. In that case, the goal is to maximize functioning and reduce suffering.

Image by Лечение наркомании from Pixabay

The Effects of Drugs on Memory

Admittedly, the term “drugs” is broad because there are several classes of them. In addition, as with alcohol, some people can use drugs without doing permanent damage to their memory. Nonetheless, taking drugs without a doctor’s prescription is a bad idea.

Let’s look at some common drugs and their effects on memory.

The Impact of Marijuana on Memory

There’s no question that marijuana is popular these days. However, with increased use (and local legalization), it’s important to understand how the drug can affect memory. According to the National Institutes of Health (NIH), there is ample evidence that marijuana use can cause memory issues. Furthermore, the earlier someone starts using the drug, and the more they use it, the greater their memory loss can be.

From these studies, we can see that, despite marijuana’s often pleasurable effects, use is not risk-free. Furthermore, animal studies demonstrate that marijuana is especially damaging when the brain is still developing, both before and after birth. 

Finally, like any drug, the more marijuana you use, the more likely you are to have side effects. For instance, marijuana can exacerbate mental health challenges. So far, the verdict is out on how much marijuana use or exposure can influence the development of mental illness in adults.

The Impact of Opioids on Memory

There’s no question that opioid abuse has become an epidemic over the last few years. Due to the illicit drug supply being mixed with other substances, we don’t necessarily get a clear view of what may be affecting our addicted loved ones. However, there’s a lot of medical literature about how various opioids affect people’s memory, both when used for medicinal purposes and with abuse.

There’s growing evidence that both opioid abuse and higher levels of licit consumption can lead to amnesia. Specifically, several studies suggest that opioids can damage the hippocampus, a part of the brain that’s responsible for memory formation. 

Furthermore, recent studies show that even chronic opioid use in a clinically-supervised setting can lead to mild memory loss. In this case, the changes are usually relatively mild, as therapeutic doses of opioids are involved. Finally, we do know that many people have mild cognitive impairments during withdrawal and early abstinence. These impairments may improve with time.

The impact of stimulants on memory

Stimulants, such as amphetamines, have a long history of helping people learn new information. Combined with the positive effects on attention, this increased recall is one reason why legal stimulants are so popular for students and others who need extra mental acuity. Furthermore, many people become creative or productive when taking these drugs.

However, as many studies demonstrate, there are some risks for memory loss long-term. For example, amphetamine use contributes to false memories and faulty retrieval. Similarly, long-term meth users can suffer from both memory lapses and psychosis.

Image by Avi Chomotovski from Pixabay

Prevention and Treatment

Whether you have friends or family suffering from addiction or are a third-party observer, you should know what drug-induced memory loss looks like. Often, in the early stages of memory loss, the signs are subtle and mostly noticeable by people who are close to the addict. This is like other causes of cognitive decline, such as dementia.

However, if you know that someone also drinks a lot or uses drugs, you should be aware that memory loss may be caused by substances. This is especially true with alcohol and stimulant abuse, where cognitive deficits are well-documented. 

When someone uses drugs or alcohol and has trouble with their memory, it’s important that they see a physician as soon as possible. A healthcare provider can diagnose and treat memory loss and any underlying conditions.

There are several kinds of treatment available. First is detox, rehab, and recovery. Usually, it’s hard for people to make progress with their memory loss unless they first get off drugs and alcohol. Better yet, this step will frequently stop the damage, even if existing problems can’t be reversed.

Another option is cognitive-behavioral therapy. This treatment can help in certain circumstances, such as if underlying mental health issues are making the patient’s memory worse. Similarly, CBT might help people learn strategies that can reduce the impact of any incurable memory loss.

Finally, sometimes medicines and supplements can help. As we mentioned before, alcoholics often have vitamin deficiencies that contribute to memory loss over time. A qualified medical professional will know if there are treatments available that may work for a particular patient’s memory loss.


There’s no question that substance abuse can have a negative effect on someone’s memory. These effects have been documented for years, and often for centuries. Furthermore, in many cases the damage is progressive.

No matter what substances someone abuses, the key is to get the problem evaluated as early as possible. This way, medical providers can identify and treat the cause of any memory loss promptly. Whether the damage is reversible or not, the earlier someone is treated, the sooner they can learn to live up to their best potential.

Finally, an ounce of prevention is worth a pound of cure. Young people need to learn about the effects and risks of substance use or abuse while they’re still young. This way, we can prevent as many people as possible from sustaining brain damage, and memory loss, from drug abuse.

Frequently Asked Questions

  1. Can alcohol-induced memory loss be reversed? Sometimes. Supplementation with thiamine helps many alcoholics recover their memory, at least to some extent. However, that’s only true until the condition progresses to Korsakoff’s psychosis. Once this happens, the damage is irreversible.
  2. Do all drugs negatively affect memory, or are some less harmful than others? It’s hard to give a simple rule, as everyone is different. However, even from one substance to another, the amount and frequency of substance use, and many individual circumstances have significant influence.
  3. How can I tell if someone I know is experiencing memory loss due to substance abuse? If someone you know seems forgetful or shows other signs of memory loss, you should encourage them to speak with their doctor. There may be other factors affecting their memory.
  4. What are some strategies for reducing the risk of memory loss in social drinking situations? The biggest thing to do is avoid binge drinking. However, anyone can develop memory problems under the right conditions, even with moderate use.
  5. How do prescription medications for memory loss interact with alcohol or drug use? Often, they will interact with each other in ways that alter the overall effect of both substances. However, only a doctor or pharmacist can advise for a particular interaction case.


Wernicke’s disease, and Korsakoff Psychosis

Similar Posts