Current drug policy is doing little to stem the tide of drug abuse in the United States. Presenting information about the neurobiology of addiction to students while they are in high school offers hope for improving policy decisions by these future voters. In addition, it provides them with a foundation for promoting safe behaviors and choices for themselves, their families, and the community. By translating what scientists are discovering through research into science that can be understood by the general public, educators offer their students opportunities to challenge old notions about drug abuse and replace them with evidence-based knowledge.
We’ve seen a paradigm shift in the past decade. Parents who used to worry about the dealer on the street or the bad kid in school are realizing that the problem may be closer to home. Other than marijuana, prescription and over-the-counter drugs are the most common drugs of abuse among high school seniors (NIDA, 2012).
Teens have unprecedented access to a much-feared and deadly classification of prescriptions, the opioids, a general term used for synthetic or semisynthetic derivatives of naturally occurring opiates. Two commonly abused prescription opioids, hydrocodone and oxycodone, are derived from naturally occurring opiates (i.e., codeine and thebaine) found in the opium poppy, Papaver somniferum.
There was a 149% increase in opioid retail sales from 1997 to 2007 (Manchikanti et al., 2012). In a 2012 study, 22.5 million people were nonmedical users of prescription drugs in the past year, with the most frequent user being between the ages of 18 and 25 (SAMHSA, 2012). Among high school seniors who admitted using prescription opioids for nonmedical reasons in the past year, 40% obtained the medications from their own unused prescriptions (McCabe et al., 2012). In 2010, the majority of these excess drugs were from emergency-room physicians (45% emergency compared to 27% from dentists and 38% from other physicians; Manchikanti et al., 2012; McCabe et al., 2012). Inappropriate prescribing practices are mainly due to inaccurate or limited knowledge regarding the risks and safety of prescription drugs and the treatment of pain (Manchikanti et al., 2012). Very few young adults seek treatment for drug abuse, either because they do not want to stop using or because they’re worried about others finding out about their abuse (Wu et al., 2011).
Opioids interact with opiate receptors on neurons found in peripheral neurons and many areas in the brain. Some of these opiate receptors are responsible for modulating the release of dopamine in the reward pathway. Dopamine levels are carefully controlled by the body. Our bodies want to make sure that the release of dopamine will result in the correct “reward” for survival-promoting behaviors (Cunningham et al., 2012). Therefore, there are inhibitory checks on the release of dopamine. Opioids bind to opiate receptors and inhibit their inhibition of dopamine release, resulting in euphoria.
Long-term use of opiates can result in addiction and life-threatening health problems. Increasing dopamine levels, resulting in a euphoric high, is one way opioids cause addiction. The body anticipates the presence of the drug by increasing the amount of catabolic enzyme available to break it down. This increase results in a shorter, less intense high, and a desire to increase the amount and frequency of use.
Cessation of opioid use also results in severe withdrawal symptoms. With regular use, the body limits the production of endogenous opioids (endorphins). Without the drug or endorphins, those going through withdrawal are in intense pain and distress, which leads to an increased need to reuse to regain “normalcy.”
Regular, long-term opioid use can lead to a severe addiction that is difficult to break, but there are other health issues associated with short-term use, especially when opioids are combined with other drugs. Drowsiness, constipation, and nausea are side effects of opioid use, but the most concerning side effect is respiratory depression. Prescription opioid use was responsible for more overdose deaths than heroin and cocaine combined, according to a CDC study of data from 1999–2011 (CDC, 2011).
So what are the solutions? How do we counter this epidemic? One strategy targets reform of prescription practices for pain management (Manchikanti et al., 2012; McDonald et al., 2012). Approaches include changing formulas, dosages, and pill types to deter or prevent abuse. Several studies have reviewed the potential for abuse-resistant and abuse-deterrent formulations (prohibiting non-oral use) of opioids to make them less attractive to users. Many of these formulas are currently in testing stages (Bannwarth, 2012; Raffa et al., 2012; Vosburg et al., 2013).
An even more promising strategy is education; policy change won’t happen without a realization of the dangers of nonmedical prescription drug use. The American Biology Teacher has given science educators unique access to translational research on this topic through the Addiction & the Brain column featured in the previous seven issues. We appreciate having had the opportunity to partner with NABT in the series and look forward to continued collaboration in the next series, on Neurobiology & Learning.
This project was funded by the National Institute on Drug Abuse, National Institutes of Health, under award no. R25DA028796. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.