Schizophrenia and Addiction

Two chronic mental illnesses, schizophrenia and addiction, are more similar than you might think. They actually produce some of the same debilitating symptoms, and can be difficult to diagnose and treat. It’s not unusual for these two disorders to occur at the same time.

There’s still more to learn about schizophrenia, but medical experts have the basics down. Research also continues into addiction, as we seek to better understand its causes. An understanding of both of these conditions relies on continued research in the area of brain science. Both disorders are also based in part on genetics, which we’re still working to understand fully.

The relationship between schizophrenia and addiction is clear, though. They can exhibit similar symptoms and occur at the same time, and should be treated together.

Effective treatments are available to manage both schizophrenia and addiction.

What Is Schizophrenia?

A severe mental disorder, schizophrenia affects about seven out of every 1000 people. Schizophrenia causes delusions, hallucinations and other upsetting feelings. Schizophrenics might be paranoid that someone is following them or “out to get them.” They also have strange or unusual ideas that make it hard for them to function in a social setting. It can be difficult for them to carry on a coherent conversation at times.

Since there’s no physical test for schizophrenia, diagnosis is based on identifying symptoms. Symptoms of schizophrenia include:


People with schizophrenia hold ideas and beliefs that are illogical and unnatural in their own cultures or situations. They hold onto these beliefs even after presented with evidence that they are wrong. They often believe other people are trying to control their thoughts, like neighbors or the people on television.

Schizophrenic delusions can also take the form of alternate identities. This is where the erroneous idea of “split personalities” comes from. People with schizophrenia may believe they’re really someone else, like a historic figure, or that they’re related to someone famous. They can become paranoid that people are out to get them, trying to cheat them, spying on them or even trying to poison them. Sometimes these paranoid delusions extend to their family members or other people they care about.


People with schizophrenia commonly hear voices that are not there, although they might also experience other sensory hallucinations as well. The phantom voices seem to come from within the person’s own head or from outside sources. Sometimes, the auditory hallucinations talk to each other and the person with schizophrenia is just a witness to the conversation.

Other sensory hallucinations can make people feel like someone is touching them when there’s no one there. They might also see objects or people that are not present. Many of these hallucinations play into the paranoia.

Movement disorders

Repetitive motions can be a symptom of schizophrenia. A person with schizophrenia might move in a way that would indicate agitation, but in fact the movements are uncontrolled, like a frantic tapping of the fingers or constant wiggling of some sort. The opposite could happen, as well. Schizophrenia might cause a complete lack of motion where the person appears catatonic, without any movement whatsoever.

Thought disorders

People with schizophrenia often find it hard to organize their thoughts into logical conversation. When they talk, their ideas and words are mixed up in a way that makes them hard to understand, and makes their conversation hard to follow. They may stop abruptly in the middle of a sentence or thought and not be able to resume, as if the thought has been taken right out of their head.

Thought disorders also cause people to make up words that carry no meaning. Generally, communicating with other people is extremely difficult.

Schizophrenia also shares some symptoms with other mental disorders. These symptoms are harder to recognize as part of a schizophrenic diagnosis:

  • Difficulty focusing on one activity from start to finish
  • Lack of facial expression or vocal intonation
  • Lack of speaking
  • Little pleasure in day-to-day activities

Without the larger symptoms, these could actually be indicative of a number of different mental illnesses. A lack of focus, for instance, is seen in attention deficit disorders, addiction and a whole list of other conditions, some of which are not chronic or serious. The inability to feel pleasure might be a sign of depression or anxiety, or another mood disorder.

These negative symptoms of schizophrenia may result in self-neglect. Schizophrenics may require help completing basic hygiene routines and other important regular functions. This severe lack of functioning can come across as lazy, but it’s actually part of the schizophrenia.

Cognitive functioning can be impaired by schizophrenia, but testing is generally required to detect the symptoms, which can include:

  • Inability to pay attention
  • Difficulty reasoning and making decisions
  • Reduced short-term memory and immediate recall

The degree of cognitive symptoms varies in cases of schizophrenia. These cognitive impairments make holding down a job and functioning in social settings extremely difficult.

It’s unusual for a child to be diagnosed with schizophrenia. Usually, the disorder is identified in young adults. Symptoms can start anytime between the ages of 16 and 30, but if no symptoms are recognized by age 45, schizophrenia is not likely to develop after that point.

Although it’s frequently associated with violence in the movies, schizophrenia does not usually produce violent behavior in individuals. People with schizophrenia are more likely to be withdrawn than aggressive. They present more of a danger to themselves than to other people. Treatment diminishes the chances of negative outcomes from schizophrenia.

The risk of suicide among schizophrenics is understandably higher than it is in the general population. The frustration of dealing with hallucinations and delusions can lead to depression. Many schizophrenics isolate themselves to avoid the embarrassment and ridicule their condition may elicit in others who are less sympathetic. When symptoms go untreated, the consequences can include unemployment, loneliness and social isolation.

Causes of Schizophrenia and Addiction

These two disorders are most closely related by their genetic component. Although rare, schizophrenia occurs most often in identical twins who have the disease. It’s also more likely to develop in people who have a first-degree or second-degree relative who suffers from the disease. Despite the strong genetic component of schizophrenia, not everyone who is related to a sufferer will inherit the disease. Also, there are some people with schizophrenia who have no family history of it at all.

The genetic component of addiction is very similar to this. Addiction does run in families, but if your father is an addict, there’s no guarantee you’ll become one, as well. There’s actually an ongoing debate about whether addiction runs in families specifically because of a genetic component, or if the environment is more to blame. People who grow up in households with one or more addict tend to develop an addiction when they’re older, but more research is necessary.

Schizophrenia is believed to have an environmental component as well, although it still requires more study. Environmental factors like malnutrition or birth traumas could contribute to developing schizophrenia, along with exposure to certain viruses and other psychosocial factors.

Just like with schizophrenia, though, addiction is not just a “genetic disease.” Not everyone who has an addict in the family goes on to develop an addiction themselves. There is some argument for a more complex physical marker for addiction, since two people can consume the same amount of the same substance and one becomes addicted to it, while the other does not.

There’s still a lot to learn about genetics, brain science, schizophrenia and addiction. Brain scans and genetic testing are still being developed to isolate and predict these diseases. In the meantime, treatment is designed to mitigate the symptoms. In time, perhaps the cause of schizophrenia and addiction can be identified and reversed.

Schizophrenia and Substance Abuse Statistics

It’s easy to see the connection between schizophrenia and substance abuse, based on the statistics. The difficulty is in assessing the exact relationship between schizophrenia and addiction.

At least 50% of all mental health patients struggle with substance abuse. A common co-diagnosis with mental illness is addiction. The top three substances of choice among the mentally ill are alcohol, marijuana and cocaine. Other drugs commonly abused by people suffering from mental disorders are prescription drugs like tranquilizers and sleep aids.

It can be difficult to tell the difference between symptoms of drug abuse and symptoms of other mental illnesses, so the common belief is that the comorbidity of addiction and mental disorders is under-reported. Men between the ages of 18 and 44 suffering from mental illnesses like schizophrenia are the most likely to abuse drugs.

The commingling of mental illness and substance abuse makes it very difficult to diagnose accurately.

Drug-Induced Paranoid Schizophrenia

There’s no doubt that drug use can play a part in a number of different mental illnesses. Drugs work in the brain to produce their effects — and, of course, that’s where mental illness takes its toll, as well.

Drugs interfere with the chemical messaging system in the brain, which is how they make you feel a certain way. The results of drug use are different according to the substance, but they all change chemical messages in your brain in some way.

The key to brain function is balance. At any moment, your brain is working to achieve a balance of brain chemicals. When there’s a shift somewhere, that tells your brain it needs to react in some way. Your reaction could be as simple as moving your hand off a hot surface, or as complicated as withdrawing from a social situation.

Drugs cause these sorts of shifts in the level of chemical messengers in your brain. There are other factors, however, that can produce the same or similar shifts in brain chemistry.

If you’re sitting in your living room and you hear the voice of your dead mother coming from the sofa, it’s the chemicals in your brain that have caused that sensation. The drugs you consumed may cause such a hallucination, or a mental disorder could have done it. If you have a mental disorder, and you have taken hallucinogens, it may be impossible to know the exact cause.

Drug abuse can create symptoms similar to those of schizophrenia, and it’s nearly impossible to tell the difference between drug-induced and chronic schizophrenia. There are, however, some differences. They include:

  • The duration of the disorder — Schizophrenia is a chronic condition that can be treated and controlled, but will never fully resolve. The drug-induced variety is generally only temporary, although it may require treatment to reverse.
  • The genetic component — Drug-induced schizophrenia does not contain a genetic component. The drugs do not alter one’s genetics to mimic those of a chronic schizophrenia sufferer. Although the exact cause of schizophrenia is not known, it clearly has a genetic basis that’s absent in the drug-induced variety.

Since schizophrenia treatment centers on reducing symptoms, it can be useful for both chronic and drug-induced cases. Although drug-induced schizophrenia is not permanent, it can take a while for symptoms to resolve. If there’s addiction involved, it will take longer, since the drug continues to be reintroduced.

Dual Diagnosis Schizophrenia and Substance Abuse

It’s not unusual for a person who is suffering from mental illness to also struggle with addiction. In most cases, it’s difficult to know which disorder came first and what their causal relationship is. For this reason, a dual diagnosis should always be treated simultaneously. For more about dual diagnosis treatment, contact 12 Keys Rehab to speak with an expert.

It’s especially important to treat schizophrenia and addiction together, partly because they produce some of the same symptoms. It’s very difficult to know if your schizophrenia is under control if you’re abusing drugs and, therefore, experiencing symptoms of drug-induced schizophrenia, as well.

In the case of schizophrenia, drug use and addiction is often the underlying disorder, which is difficult to detect. The symptoms of schizophrenia produce anxiety and paranoia. It’s not uncommon for someone suffering from this disease to attempt to self-medicate.

Common drugs like alcohol, nicotine and marijuana are often believed to produce a calm or even euphoric state. There are many recreational drugs that people with mental disorders use to try to mitigate their symptoms, or just escape the discomfort of their lives. In addition to the anxiety, schizophrenics are often lonely and isolated and may seek stimulation or mood enhancement.

The symptoms of schizophrenia can become so severe that those are what a person seeks treatment for. They are certainly more pronounced than the signs of drug addiction. Unfortunately, some schizophrenic treatments do not work well when mixed with other drugs. Treatment for schizophrenia when a dual diagnosis actually exists can be long, slow and frustrating.

The underlying drug addiction needs to be treated in order for the treatment for schizophrenia to be really effective. Schizophrenia is a chronic condition that requires continual treatment to remain under control. Drug abuse disrupts that treatment and exacerbates the symptoms of schizophrenia. When these two disorders coexist, it’s impossible to make progress without addressing them together.

Can Alcohol Cause Schizophrenia?

Many people who are aware of the symptoms of schizophrenia ask, “Can you drink alcohol if you have schizophrenia?” Alcohol, like any other drug, cannot cause schizophrenia. It can, however, make your situation worse.

Alcohol is a common, and very legal, recreational substance, and it’s often used for mood enhancement. The long-term effects of alcohol on your body and brain are anything but positive. It can produce a euphoric feeling or high at the time of consumption and in certain quantities. That high is always balanced by a low when the alcohol leaves your system.

This cycle of high and low can be especially detrimental to someone suffering from schizophrenia. People with schizophrenia tend to be sullen and even withdrawn. The high of alcohol may seem like a good antidote to their low mood. The withdrawal, or hangover, however, can compound their low mood and contribute to depression.

In larger quantities, abusing alcohol can lead to severe withdrawal symptoms that include:

  • Hallucinations
  • Irritability
  • Delusions
  • Confusion
  • Seizures

Anyone who suffers from schizophrenia will probably want to avoid all of these possible conditions. The symptoms you experience as a result of your schizophrenia are bad enough, and can hopefully be controlled with treatment. It doesn’t make sense to risk escalating any of your symptoms or causing new ones.

Some other common substances to avoid if you have schizophrenia are caffeine, nicotine and sedatives. Caffeine causes anxiety, especially in people already prone to it. One of the challenges for people with schizophrenia is managing their anxiety, which is often caused by the presence of their other symptoms.

Nicotine use is associated with depression. It’s a drug that affects the pleasure centers of the brain, which is why it’s so addictive. People suffering from schizophrenia tend to experience mood disorders and are at greater risk for depression. It’s a good idea to avoid using substances that work in the brain’s pleasure centers, if possible.

Depression is also a risk with sedative use, abuse and withdrawal. Like alcohol, sedatives can cause some unpleasant and even dangerous side effects upon withdrawal. Withdrawal symptoms from sedatives, like anxiety, depression, dizziness, hallucinations and headaches can last up to a year or more.

Is Schizophrenia Caused by Drug Abuse?

Schizophrenia is a chronic condition that, at its core, is genetic in nature. It’s much more complicated than that, and the exact cause is still unknown. We do know that drug abuse can cause people who do not have schizophrenia to exhibit the same symptoms. It can be a scary situation to recognize these symptoms in your friend or loved one. The only way to be sure it’s not a chronic disease is by seeking a professional diagnosis.

The chronic disease schizophrenia cannot be caused by drug abuse alone. While schizophrenics and those who do not suffer from this genetic-based disease can exhibit the same symptoms under certain conditions, substance abuse cannot create the genetic alterations that are the markers of schizophrenia.

Drug abuse does, however, tend to exacerbate the symptoms of schizophrenia in people who already suffer with the disease. It’s a good idea to avoid drugs and alcohol if you have schizophrenia and stick with your prescribed treatment.

Learn More

If you suspect you’re suffering from schizophrenia, whether it’s drug-induced or chronic, contact 12 Keys Rehab today. Our compassionate and knowledgeable staff can answer all of your questions about these potentially co-occurring conditions. We have the experience and capacity to treat this or another dual diagnosis compassionately and effectively.

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Proper diagnosis and simultaneous treatment of schizophrenia and addiction are extremely important, and at 12 Keys, we’re fully equipped to help you with both.

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