Inside the Intuitive System: Craving is an Early Warning Sign for Opioid Relapse

Opioid use is an extremely a difficult problem to overcome. During work on a pilot project from 2017-2019 to increase the availability of medication-assisted treatment (MAT) for opioid use disorders in rural areas of Colorado, we heard patients say things like "I don't have the willpower to resist opioids," or "I wish I were a stronger person." These statements reflect people's desire to change while also conveying the difficulty of changing opioid use. People often say that they don't choose to use opioids, rather they feel that they must use them in order to maintain daily functioning. The moral model of substance use treatment ("just say no to drugs") misses this important piece of the experience for people who are already using. And given that about three-quarters of people in our MAT project started their pattern of use with prescription pain medication, they may not have felt they had a choice originally either -- they use opioids now because their doctor prescribed them previously. As a result of this connection between opioid addiction and prescription pain medication, the disease model of addiction does not fit well for many people either -- it's hard for them to trust health care professionals who in their view got them hooked on drugs in the first place.

By the time people are physiologically dependent on opioids, they are generally not receiving a strong pain-reducing response from the drugs. Instead, people say they take opioids simply to feel normal. Chronic opioid use leads the brain to create more receptors for opioids, which then need to be filled just to maintain one's baseline level of functioning. Furthermore, the same opioid receptors are  involved in people's experience of everyday pleasant activities, which means that normal happiness is harder to come by because it delivers such a small level of opioid stimulation in comparison to drugs. Finally, a second brain system involving dopamine also gets activated by drug use, leading to euphoria and causing reward-seeking behavior (the dopamine response is centered in the lower-brain nucleus accumbens, which is also a primary driver of behavior within the Intuitive System). The brain's dopamine response to opioids is more akin to excitement or novelty than to pain relief, and is experienced as rewarding in a different way from the pain-relieving opioid effect. Like opioid receptors, dopamine receptors increase in the brain as people use drugs for a longer period of time, leading to a more intense desire for the experience and a need for higher levels of stimulation to achieve it.

The desire for opioids, often called craving, is an aspect of addiction that many people find especially difficult to overcome. Research shows that a sudden increase in craving often precedes an opioid relapse. The strength of this relationship is dramatic, increasing in the chances of relapse among patients who report strong cravings to 43%, compared to only 26% among those who do not. People who overuse prescription opioids have stronger cravings, lower pain tolerance, and more psychiatric symptoms than those who do not. Because of the dopamine response involved in craving, even minor cues that have been associated with past drug use can present significant risk factors for relapse. Even behavioral cues like a needle or a pill bottle might eventually provoke a low-level dopamine response, becoming part of the experience or a cue for drug-using behavior: In another study, patients who were deliberately exposed to drug-related situations or paraphernalia had higher cravings as a result, with a stronger effect for heroin than for prescription opioid medications. Finally, MAT dramatically reduces cravings within the first month, which may in part explain its effects.

In a recent project to improve services for patients with opioid use disorders, CU Doctor of Nursing Practice graduate Dr. Audrey Strock implemented regular assessment of patients’ cravings at four outpatient psychiatric practices. She used the Opioid Craving Scale as a way to measure patients' response to treatment at every visit with their psychiatric nurse practitioner. When craving increased, it meant that the patient might need extra support to maintain abstinence from opioids. Even though patients in this study were already relatively stable in treatment at the outset, their average craving score decreased by about 75% over 3 months of treatment, and remission rates improved from 80% to over 95% during the course of the project. This project further illustrates how attending to opioid cravings can improve the process of care.

The CU College of Nursing was recently named to lead a new $5 million initiative from the Colorado state legislature targeting the state’s opioid epidemic. Like the recent 2-year pilot, the new program’s goal is to offer more medication-assisted treatment (MAT) for opioid use disorders through NP- or PA-led clinics in rural areas of Colorado. MAT has two components, behavioral counseling plus a medication to block opioid receptors in the brain. In a previous blog post, I talked about how these two elements work together to reduce people’s desire for opioids while also increasing their coping skills to avoid opioid use. People can learn coping skills to tolerate the experience of craving, and need to be reassured that eventually the brain will return to baseline levels of opioid and dopamine receptors so that they can enjoy normal pleasant experiences once again. MAT neither blames patients for their addiction, nor suggests that they need to take a different drug indefinitely as a result. Instead, it creates a space in which the most destructive and self-perpetuating aspects of opioid addiction such as cravings are held at bay, while the patient practices new skills to avoid opioid use in the future.