Do drugs cause mental illness?

By David Joel Miller, MS, Licensed Therapist & Licensed Counselor.


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What is the connection between drugs and mental illness?

By drugs here I am talking about illegal or street drugs, though prescription drugs can be misused and create the same effects. The relationship between drug use and mental illness is not so clear-cut as first glance would suggest. Not all mentally ill people use street drugs and many of them did not try street drugs until after they had an episode of mental illness.

1. Drugs can cause a mental or emotional problem.

There is a clear connection between some drugs of abuse and some mental emotional and behavioral disorders. We call these problems “substance-induced disorders.”

That connection can include emotional problems caused by prescription medications. Stimulant abuse, especially Methamphetamine can cause full-blown psychosis. Currently, we think there are several connections between Marijuana and psychosis. That would be a subject for another post, maybe even a book.

Drugs of many kinds can cause or exacerbate depression and other mood disorders. They can also cause or increase anxiety. There are several ways drugs can cause an emotional problem.

A. Intoxication.  People may behave differently when under the influence. Alcohol is an easy to see case of this. So is Phencyclidine abuse. People who rarely have caffeine may have an intoxication reaction if they suddenly ingest a large amount.

B. Withdrawal – They may have problems when they are withdrawing from drugs. Heroin or opiate-dependent people get very physically ill. Meth users crash, become depressed, and sleep for extended periods of time.

C. Substance-induced disorders. They may also develop long-term issues as a result of drug use. Meth-induced psychosis is becoming more common in my area. The central valley of California was described in a recent news article as “The Meth Capital of America.”  It is clear that people under the influence of meth can be psychotic. It is also beginning to be clear that the psychosis does not always go away once they stop using Meth. The way in which Meth damages some parts of the brain more than others, those changes on brain scans, are making some researchers look at specific structures in the brain as possible causes for many cases of psychosis.

There is a difference in the hallucinations experienced by drug abusers and those reported by people with psychosis. People with Schizophrenia most often report hearing voices, auditory hallucinations. Meth-induced psychosis is most often visual. They see Meth monsters or pet shadow puppies. Meth users also report that their visions do not go away when they close their eyes. So while the two types of psychosis are similar they are not identical. Maybe future research will answer all these questions.

2. People with a mental or emotional problem may be more attracted to a particular drug.

People with chronic episodes of depression may be attracted to stimulants. The quick lift of caffeine or cocaine can make your depression more manageable – temporarily, very temporarily. Freud, the father of modern psychiatry experimented with Cocaine as a way to treat depression and produce overall happiness. What we found out was that while there might be a lift of mood, there was always a crash afterward.  So the use of stimulants is no longer accepted practice because it leaves the user in a worse state than where they started.

Other examples of ways in which people with particular mental illness might be attracted to a particular drug are the way in which people with psychosis, meaning schizophrenia, schizoaffective disorder, sometimes Bipolar disorder, etc. are highly attracted to smoking. The nicotine may have some effects on the disorder. I am not suggesting anyone should take up smoking; the bad health results far outweigh the current pleasant feelings.

While we are on the subject of smoking, however briefly, I need to mention one report I read that said that more than half the cigarettes smoked in America are consumed by people with a DSM-4-TR diagnosis. Some writers have suggested that cigarette companies have deliberately added things and marketed their products to people with mental illness and substance abuse disorders. I do not know if that is true but I do know many clients with severe mental illnesses and substance abusers are heavy smokers. Remember this blog is called counselors soapbox for a reason.

In residential substance abuse facilities, we find that many clients entering treatment had the symptoms of a mental or emotional disorder before they ever started abusing substances. One theory to explain this is that some substance abusers are “self-medicating.”

3. Giving up your drug of choice can result in severe depression, anxiety, and other emotional problems.

Most long-term users get closer to their drug of choice than to other people. All their friends are involved with the same drug. So once they quit they are very alone.

This process of giving up your drug of choice is a lot like grieving over the loss of a family member or friend. The alcoholic might tell you that women come and go but “Sherry is always there.” The Meth user describes their effort to quit as “Crystal is always there.” And they remind us that “She,” whichever she that is, is jealous and didn’t want them having any other relationships.

So there you have some thoughts on the relationships between drugs and mental illness. There are other relationships but I need to stop for now.

Hoping to hear from you about your thoughts on the topic of the connections between drugs and mental illness.

Staying connected with David Joel Miller

Seven David Joel Miller Books are available now!

My newest book is now available. It was my opportunity to try on a new genre. I’ve been working on this book for several years, but now seem like the right time to publish it.

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Baldwin struggles to survive life in a post-apocalyptic world where the government controls everything.

As society collapses and his family gets plunged into poverty, Baldwin takes a job in the capital city, working for a government agency called the Story Bureau. He discovers the Story Bureau is not a benign news outlet but a sinister government plot to manipulate society.

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What would you do if you found a letter to a detective describing a crime and you knew the writer and detective were dead, and you could be next?

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