Patients in methadone maintenance treatment (MMT) exchange a variety of prescription drugs—but little is known about why this happens, and how common it is.

Given the risks of this practice—drug interactions, side effects, addiction, antibiotic resistance, birth defects, and possible interruption of MMT—a group affiliated with Butler Hospital and Brown University, Providence, RI, decided to find out. They published their findings in the January 1, 2013 issue of Drug and Alcohol Dependence. From December 2008 through January 2012, the team screened 767 individuals who enrolled in a smoking cessation trial in nine MMT sites in Southern New England. Characteristics of the 315 participants recruited were:

• Average age 40 years
• 49% male
• 79% non-Hispanic white, 12% Hispanic, 2.5% black
• Health insurance: public, 56%; private, 14%
• 42% received disability payments
• Average length of methadone treatment, 154 weeks
• Past-30-day use of heroin, 7%; cocaine, 8%

Study Results

About 79 percent of participants had been prescribed at least one medication during the previous year. The drugs include allergy medications, antibiotics, blood pressure medications, erectile dysfunction drugs, antidepressants, tranquilizers, and drugs of abuse: sedatives, medications for ADHD, sleep medications, pain medications, and Suboxone (buprenorphine and naloxone).

About 20 percent of participants reported sharing their medication, and almost 40 percent said they had used medication not prescribed to them. While these rates may not be significantly higher than those in the general population, they represent a substantial risk to MMT patients. According to the Centers for Disease Control and Prevention (CDC), people with substance abuse histories are particularly vulnerable to overdose and adverse events related to illicit prescription drug use. Moreover, the authors note that MMT confers significant health benefits, and continued use of non-prescribed prescription medications may interrupt treatment.

Medications most often shared (given or sold) and received (borrowed or bought) were those with abuse potential—pain medications, sleep medications, and sedatives.

Sources of Drugs of Abuse

^aAttention deficit hyperactivity disorder.

^bBuprenorphine and naloxone.

As the table shows, patients generally received medications of abuse from friends or family, rather than buying them. Of interest, the only exception was Suboxone; 40 percent of patients (n=16) received the buprenorphine and naloxone medication from friends or family, and 60 percent (n=24) bought it on the street. In contrast, 66.7 percent of patients received their ADHD drug from friends or family, and 33.3 percent bought on the street; the corresponding percentages for pain medications were 54.9 from friends or family, 42.3 from street purchases, and 2.8 from acquaintance purchases.

The authors commented that the frequent receipt of buprenorphine from nonmedical sources “is consistent with an earlier study of opioid users, where 76% reported that they had used illicit buprenorphine.”

The authors did not list the specific prescription sedatives and pain medications bought on the street, but the former group includes benzodiazepines and barbiturates, and the latter group, opioids and nonsteroidal anti-inflammatory drug (NSAID) combinations.

Reasons for Exchanging Medications of Abuse

The only factor significantly associated with sharing drugs of abuse was younger age.

Four factors were significantly associated with receiving medications of abuse: younger age, being male, recent use of heroin or cocaine, and financial hardship.

The authors noted the important impact of financial hardship and low socioeconomic status on sharing and receiving. In the previous 6 months, 21 percent of the study population had at times gone without food, clothing, or housing to pay for medicine, and 8 percent had gone without needed medical care to pay for those necessities.

Moreover, the MMT population “has high rates of being uninsured or underinsured”—thus is more likely to share and receive various medications, not just illicit opioids. Many participants had public rather than private insurance, so “medication access, continuity, and affordability may still be a concern,” the authors said.

Value of the Study

This early study sheds light on the high rate of medication exchanges among MMT patients, and on some characteristics that lead to sharing and receiving—in particular, vulnerability, financial hardship, “and the need to self-medicate a physical health problem.”

These reasons underscore the need for better approaches to help this at-risk population. The authors note that while many resources for studying, defining, and understanding prescription drug exchange focus on trafficking, “doctor shopping,” and internet purchase of illegal prescriptions, prescription medication sharing also contributes to illegal use.

Reasons for sharing and receiving need further examination both to prevent the exchange of prescription drugs and to “maximize care to a vulnerable and underserved population,” the authors said.

    *     *     *

Caviness CM, Anderson BJ, de Dios MA, et al. Prescription medication exchange patterns among methadone maintenance patients. Drug Alcohol Depend. 2013; 127(1-3):232-238. doi: 10.1016/j.drugalcdep.2012.07.007.