Gabapentin Abuse: Some Questions and Answers
Over the years, substance abuse trends in the states have shift from one drug to another as new policy solutions make previously abused drugs more scarce. Over the past decade, gabapentin has emerged as a drug of concern. Gabapentin, the generic for Neurontin, is a medication that was approved by the FDA in 1993 and is approved to treat epilepsy and nerve pain caused by shingles. The IMS Institute for Healthcare Informatics reported that 57 million gabapentin prescriptions were written in the United States in 2015, which is a 42 percent increase from 2011.
How is gabapentin being abused?
Patients that abuse the drug describe experiences such as euphoria, improved sociability, a marijuana-like high, or even a zombie-like effect. Patients can abuse the drug by taking higher than prescribed doses of the drug to achieve the experiences that were just described. Gabapentin can potentially be lethal at toxic doses, and unfortunately there is no antidote for it as there is with opioids. The first published report of a patient taking excess gabapentin to commit suicide occurred in 2011.
It has also been reported that patients mix the drug with other substances to achieve a high. According to the Kentucky Injury Prevention and Research Center (KIPRC), the number of gabapentin related overdose deaths from 2012-2015 in Kentucky increased from 9 to 173. However, KIPRC notes that the increase in gabapentin related deaths could be due to increased testing for the drug in 2014 and 2015. Of the 245 deaths between 2012 and 2015, fewer than 5 of the deaths listed gabapentin alone or in combination with alcohol, with no other drugs present in the body. Thus, the majority of gabapentin related overdose deaths involved gabapentin being mixed with other substances. The table below shows the substances most commonly mixed with gabapentin in overdose deaths between 2012 and 2015:
KIPRC listed gabapentin as fourth in the top ten drugs that contribute to overdose deaths in Kentucky in 2015.
How were we first alerted that gabapentin could possibly be abused?
In 2004, a correctional facility in Florida found that some of the inmates were snorting the powder inside the capsule, and that most of the gabapentin prescriptions were not in the possession of the intended patient. This issue was brought to light in Kentucky when a cohort study of 503 Kentucky patients found that 15 percent of the respondents stated that they used gabapentin to get high in the past 6 months. The two major sources that the patients used to get gabapentin were physicians (52 percent) and drug dealers (36 percent).
In response to concerns about gabapentin abuse and diversion, a survey of 1,769 pharmacists in Kentucky was conducted by Trish Freeman and James Blackmer at the University of Kentucky College of Pharmacy. In this survey, 64 percent of respondents agreed or strongly agreed that patients frequently seek multiple prescribers or “doctor shop” to obtain gabapentin. 72 percent of the respondents supported gabapentin becoming a controlled substance in Kentucky.
Federally, gabapentin is not a controlled substance. Thus, there are less barriers in place for patients to get this medication than for opioids. Even though it is not a controlled substance at the federal level, states can choose to make the drug controlled. As of July 2017, Kentucky is the only state to place this drug on their controlled substance list.
How does placing a drug on the controlled substance list tighten the barriers to get the drug?
Being a controlled substance requires that the drug be reported through a state’s prescription drug monitoring program, or PDMP. A PDMP allows prescribers and pharmacists to see all controlled medications that a patient receives, which in turn will alert them if a patient is possibly abusing these medications. Also, being a controlled substance requires that the prescription has a shorter expiration date. This means that the patient has to be evaluated by their prescriber more often to ensure that they truly have a need for the medication. In Kentucky, Gabapentin is a Schedule V medication, which limits prescriptions to 5 refills and a 6 month expiration date.
What are other safeguards against abuse that states can put in place?
Ohio, Virginia, Massachusetts, Minnesota, and Wyoming all require that pharmacists report gabapentin prescriptions to their respective PDMPs even though the drug isn’t a controlled substance in these states. Also, Illinois requires that long term care facilities report the dispensing of gabapentin to their PDMP. PDMP monitoring makes it easier to identify possible abusers.
Where is gabapentin likely to be prescribed?
CVS reports that 43 percent of the patients that fill gabapentin prescriptions at their pharmacies are over 60 years of age. CSG analyzed Medicare Part D data to examine the use of gabapentin in this age group in individual states. Anyone age 65 or over is eligible for the prescription drug benefit, Medicare Part D. In 2015, there were 4.8 million Medicare Part D patients who received gabapentin. The percent of Medicare Part D beneficiaries from each state that filled gabapentin prescriptions in 2015 were calculated and are shown in the map below. The national average was 12.3 percent.
The top five states are:
- West Virginia-16.3 %
The bottom five states are:
- Hawaii- 5.9%
- New Jersey- 7.9%
- Vermont- 9.9%
- Maine, New York, South Dakota- 10.3%
Overall, data for Medicare Part D beneficiaries suggest that a large amount of gabapentin is being prescribed and filled, and that the rates among states differ by magnitudes of two to three times. The state with the highest rate, Kentucky, has in fact taken an aggressive action to safeguard against abuse, making gabapentin a controlled substance. Several states require that prescriptions for the drug be reported to the state’s PDMP. Ultimately, other states may want to look to these policy solutions to minimize the abuse of this drug.