When visiting a healthcare provider or specialist for the first time, one of their opening questions may be about your family medical history. You will most likely mention serious conditions, such as cancer and diabetes. However, if you have a family history of substance abuse, it may warrant mentioning during your visit as well. There is a link between drug and alcohol addiction and your genetic makeup, as well as your environment, lifestyle, and experiences – making substance use disorders complicated conditions to treat.
What Is Addiction?
There are three primary factors that typically define addiction, says Thomas Bales, PA-C, physician assistant at Harbor Psychiatry & Mental Health. “It comes down to cravings (the powerful desire to use the substance), dependence, and loss of control – meaning the substance starts to take priority over all other aspects of life,” he explains.
It can often be difficult to distinguish between substance addiction and misuse, but compulsively seeking out drugs or alcohol is a main marker for addiction. For example, if you have a tendency to indulge in one too many glasses of wine during your weekly work happy hour, that may be a situation of alcohol misuse. If you find yourself consumed with thoughts of drinking, and you resort to sneaking drinks during the workday, then this may be an issue of addiction.
Technically, the scientific community prefers to use the term "substance use disorder" rather than addiction or abuse. However, you may hear those terms used interchangeably in more colloquial settings.
Hereditary vs. Genetic Contributions to Addiction
While there’s no single addiction gene that makes someone destined to have drug or alcohol concerns, using substances can affect an individual's neurotransmitters – the chemical messengers that send signals to nerves around the body.
“Each drug may affect different neurotransmitters and neural circuits, but most drugs of abuse eventually activate the mesolimbic pathway, otherwise known as the reward pathway,” says PA Bales. Polymorphisms (genetic variants) in your genes can change how your neurons respond to substances, and along with other factors may change how you experience this reward.
Similarly, Bales adds that there can be a hereditary component to drug and alcohol addiction, passed down from parent to child. “Studies have shown in certain situations that nicotine dependence can be hereditary as well as alcohol,” he says. “It’s important to know how genes play a role in addiction and which [genes] those are.”
Mental Health Concerns and Addiction
“When it comes to addiction, there are both physical and mental health consequences,” says PA Bales. This is especially true for those battling comorbid compulsive disorders, anxiety disorders, bipolar disorder, and depression.
It can often be difficult to know which came first, the mental health concern or the addiction. Drug and alcohol use may lead to a mental health concern. Meanwhile, many individuals use drugs or alcohol to take away negative feelings associated with these disorders. “There is a strong relationship between mood and thought disorders and addiction, going both ways,” adds Bales. “This can lead to people using substances like drugs and alcohol to self-medicate.”
The Neuropsychology Behind Drug and Alcohol Addiction
Research published in Lancet Psychiatry found that substance addiction works in three major steps in the body, each with its own psychological components. Here's how it breaks down:
- There is the initial binge or intoxication step, which creates a feeling of positive reinforcement in an area of the brain called the nucleus accumbens. “This is what then causes an individual to satiate [and replicate] this feeling at whatever cost,” says Bales.
- As a user starts to go through the second step, known as the withdrawal stage, the limbic system in the brain, responsible for emotions and memory, may be affected. Here, Bales says signals are sent to the brain which then triggers an anxious response throughout the rest of the body.
- Last, a craving and an anticipation stage in the prefrontal cortex of the brain is triggered, which can create positive emotions linked to substance use, and may be one of the biggest factors responsible for relapse.
Positive and Negative Reinforcement
Drugs and alcohol can become addictive very quickly because they are linked to both positive and negative reinforcement. For example, substances can offer positive reinforcement, by flooding the mesolimbic pathway and leading to feelings of pleasure. Substances also offer negative reinforcement. For example, Bales explains that individuals with compulsive disorders may use substances to decrease the negative feelings associated with compulsion.
The capacity of these substances to increase drug use and drug seeking behavior through both these reinforcement pathways can potentially be dangerous precursors to addiction.
Other Factors That Can Affect Addiction
“Genetics, your environment, lifestyle, and past experiences all play a part in your overall mental health and wellness,” says Bales. Under this idea of the Mental Health 360™, these elements can also play a part in drug and alcohol addiction.
One groundbreaking study clearly demonstrated the critical role of environment, and how your surroundings can make you more or less likely to misuse drugs and alcohol. In the late 1970s, Bruce K. Alexander from Simon Fraser University in Canada created a "Rat Park" where rats had ample space, toys, and a chance to socialize. Other rats were kept isolated in small cages. The rats living in Rat Park were far less likely to drink water with highly addictive morphine, whereas the separated rats were much more likely to drink the morphine water. It's clear that many factors can affect addiction, not just your genes.
Managing Addiction and Mental Health Condition(s)
It can be difficult to tackle a dual diagnosis of addiction and a mental health disorder. Speak to your healthcare provider about exploring treatment options, and discuss medication options such as serotonin reuptake inhibitors (SSRI) like sertraline (Zoloft) or escitalopram (Lexapro), which may be used for comorbid depression.
If your healthcare provider suggests a medication treatment option, it is important to note that certain genetic variants can make mood disorder medications less impactful. For example, an SLC6A4 gene mutation in the body may mean that taking an SSRI for depression may have side effects and/or the medication(s) may not work as effectively.
“This is where genetic testing can be helpful,” says Bales. “Rather than trying an SSRI and increasing the dose, a healthcare provider with this information available to them can start with a more appropriate medication. Instead of using trial and error to find a medication and dosage, genetic testing can help find a more effective option right away.”
Genetic testing can improve our understanding of how an individual may respond to different treatment options, and help healthcare providers tailor medication(s) and dosage choices.
When appropriate, Bales recommends the Genomind® Professional PGx Express™ as a way to shed light on any genetic variants that could impact your treatment response, and find appropriate medication(s) more quickly. The pharmacogenetic (PGx) assay from Genomind looks at 24 genes related to mental health treatment so that your clinician can identify what medications may be more or less likely to relieve symptoms of your mental health concern and support management of your substance use disorder. This PGx testing provides guidance across 10+ mental health conditions and 130+ medications to help clinicians determine:
- Which medications may be more or less likely be effective
- Which medications may have a greater or lower risk of side effects
- How you metabolize medications for personalized dosing guidance
The Genomind® Professional PGx Express™ requires a prescription. Learn more about it here.
Are You Getting Appropriate Help for Your Addiction?
Drug and alcohol addiction can have a genetic component, but other factors may also lead to substance use disorders. Environment, lifestyle, and personal experiences all play a role in your overall mental health and wellness. Learning about your genetic profile and how other factors may interact with your genetic profile can give you personalized treatment options that may help you and your clinician manage both your mental health concerns and your addiction.
About the Contributor
Thomas Bales, PA-C provides compassionate & comprehensive care at Harbor Psychiatry located in beautiful Newport Beach, CA. He can be found sharing his wide range of experiences with students as an adjunct assistant clinical professor for the MSPAS program at Bryant University. Additionally, he serves as a clinical preceptor to PA students from various academic programs across the country. He enjoys giving lectures on various topics including neuroscience, psychiatry and general medicine.