Cross addiction and co-addiction both complicate recovery from substance abuse disorder because they involve multiple addictions.

In this article, we’ll take a close look at the definition of cross addiction and co-addiction, how commonly they occur, how they impact treatment, and more.

Let’s start with the basics: What are multiple addictions, and how common are they?

Defining Addiction and Multiple Addictions 

The National Institute on Drug Abuse (NIDA) defines addiction as “a chronic, relapsing brain disease that is characterized by compulsive drug seeking and use, despite harmful consequences.”

Essentially, an addiction must be compulsive, and an addict will continue using even when faced with negative consequences. These consequences may impact the addict’s career, finances, health, and relationships.

Recovery from addiction is possible, but it’s extremely challenging for many reasons. One reason is that addicts frequently have multiple addictions, whether to substances or behaviors. People may be addicted to gambling, shopping, sex, pornography, overeating, or even particular relationship behaviors.

There’s no concrete data on how many addicts suffer from multiple addictions, but many treatment experts say they see polysubstance abuse more frequently than addiction to just one substance. Almost 80 percent of sex addicts, for instance, struggle with multiple addictions.

Why Are Multiple Addictions So Common?

There are several reasons that multiple addictions (like cross addiction and co-addiction) are such a common occurrence. People can have “addiction vulnerability,” which is a genetic, physiological, or psychological predisposition to engage in addictive behaviors.

Addiction can be rooted in genetics, traumatic experiences, anxiety, depression, and other painful or uncomfortable emotions. As a result, addicts feel a compulsion to use substances or pursue dangerous behaviors that stimulate the brain’s reward center.

When we engage in certain life-sustaining activities, like eating or sex, the brain’s reward circuit is activated, reminding us to repeat these important activities again and again. Unfortunately, drugs activate this same reward circuit, and they do it more powerfully. Some drugs of abuse release 2 to 10 times the amount of dopamine that natural rewards (like eating and sex) do.

Ultimately, it is not just the substance that people become dependent on, but the euphoric “high” that the substance produces. This same high can be produced by other substances, as well as by intense excitement, pleasure, or even fear, often leading to experimentation with other drugs and risk-taking behavior.

Because drugs flood the brain with dopamine, the brain eventually responds to long-term drug use by producing less dopamine. Now, the addict’s ability to feel pleasure is reduced, leaving the individual feeling flat and depressed. This motivates addicts to seek out more powerful highs and take greater risks, which can result in the development of multiple addictions.

Combined with the fact that abusing substances leads to impaired judgement and reduced inhibitions, it’s not surprising that so many individuals grapple with addiction to multiple substances.

Now we’ll explore two specific types of multiple addiction: cross addiction and co-addiction.

What Is Cross Addiction?

In simple terms, cross addiction is the idea that someone who is addicted to one substance is more vulnerable to becoming dependent on another substance (or behavior).

Cross addiction does not mean that someone is addicted to multiple substances or behaviors at the same time, although this is possible. More often, cross addicts focus on one addiction at a time. Individuals may become addicted to one substance while recovering from addiction to another.

For example, someone with a pornography addiction may seek help or decide to stop. But because the underlying issues at the root of the porn addiction were not treated, the individual may now turn to another substance, like alcohol, in an effort to numb painful emotions.

It’s also important to note that the brain cannot tell the difference between substances. For this reason, some experts say that experimenting with a new substance may lead a recovering addict to relapse. A recovering alcoholic who is given pain medication, for instance, may abuse this medication and/or relapse with alcohol. The same may happen to a recovering alcoholic who is treated for anxiety with benzodiazepines.

However, empirical evidence on cross addiction is mixed. It does appear that when an addict’s underlying issues are not addressed, he or she is more likely to struggle with other addictions (or relapse) in the future.

On the other hand, a recovering addict who has also sought counseling or therapy and has appropriate coping strategies may be able to avoid cross addiction.

What Is Co-Occurring Addiction?

Unlike cross addiction, co-occurring addictions happen simultaneously. For instance, someone may use one substance to balance out the negative side effects of another. An individual who is addicted to pornography may use a substance to reduce inhibitions or feelings of shame.

In the addict’s mind, these co-occurring addictions become powerfully associated. They are often hesitant to engage in one behavior or substance without the other.

How Addictions Interact

In a 2005 paper titled “Bargains With Chaos: Sex Addicts and Addiction Interaction Disorder, Dr. Patrick Carnes and his colleagues Robert Murray and Louis Charpentier identified eleven ways that co-occurring and cross addictions develop.

Although the paper focused specifically on interactions between sex addiction and other addictions, the findings of Carnes and his colleagues can apply to other co-occurring and cross addictions as well.

Below, we’ll take a brief look at some of the terms outlined by Carnes, Murray, and Charpentier.


When using a particular substance or engaging in a certain behavior, an addict may feel intense feelings of shame, guilt, or disgust.

In response, some addicts may numb these uncomfortable feelings with an additional substance or behavior.


Addictive substances and behaviors stimulate the same neural pathways, so engaging in multiple addictions at once can intensify the “high” an individual experiences.

When someone uses one addiction to intensify another, it’s called “fusing.” This is common among sex addicts, who may use substances to lower inhibitions, improve performance, or amplify sensations.


Similarly, an individual may rely on one addiction to reduce inhibitions related to another addiction.


At other times, an addict may view one addiction as “the lesser of two evils” and indulge in this addiction in order to avoid another. Often, this method does not work, and the addict instead becomes addicted to multiple substances or behaviors.

As addictions interact with one another for various reasons, the individual’s substance abuse issues intensify. Reward centers are stimulated even more, the ability to experience pleasure naturally is reduced, judgement is impaired, and cravings grow even stronger.

Recovery From Cross Addictions and Co-Occurring Addictions

It’s not impossible to recover from cross addictions or co-occurring addictions, but it certainly is more complicated.

First, it’s essential that treatment for substance abuse includes therapy or counseling. Childhood trauma, depression, anxiety, or other painful emotions must be addressed. If these underlying issues are ignored, it’s very likely that the individual will relapse or develop another addiction in the future.

Additionally, every addiction that an individual has must be treated. Because these addictions interact and because they stimulate the same pathways in the brain, it’s impossible to fully recover from one addiction without recovering from all addictions.

This can present a problem, as some individuals engage in what Carnes and colleagues call “masking.” Someone may acknowledge an addiction to alcohol, for instance, while hiding that he or she also suffers from a gambling addiction.

During treatment, it must be made clear to the individual that all trauma, co-occurring mental disorders, uncomfortable emotions, and addictions need to be addressed. Otherwise, lasting recovery is highly unlikely.


It’s very common for addicts to suffer from multiple addictions, whether simultaneously or at different points in life.

Co-occurring addictions happen at the same time and are inextricably linked in the addict’s mind. Cross addiction is the theory that an addict is more vulnerable to becoming addicted to other substances in the future, often while in recovery from one substance or behavior.

Although treating multiple addictions is complicated, it’s possible if all addictions are addressed. Counseling or therapy is also necessary to address mental disorders, trauma, or difficult emotions. The individual needs to learn about triggers and healthy coping strategies.

If the individual is thoroughly treated and develops a solid aftercare plan, a healthy, happy, and addiction-free life is possible.

To learn more about co-occuring addictions and cross addictions speak to one of our addiction specialists by calling 1-888-919-2619.

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