05/5/17

The Evolution of Neurontin Abuse

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Not long ago a Columbus Ohio television station, Fox 28, noted the Ohio Substance Abuse Monitoring Network (OSAM) issued an alert about a pill doctors say is now being abused by heroin addicts. It’s not an opioid or a benzodiazepine; it’s not even a controlled substance. Yet it was the number one dispensed medication in Ohio in December of 2016, “at a 30 percent higher rate than Oxycodone.” Can’t guess? Would you be surprised to know that drug was Neurontin?

In February of 2017 OSAM published “Neurontin© Widely Sought for Illicit Use.” The OSAM report said Neurontin (gabapentin) was first identified as drug of abuse by law enforcement in January of 2014, in Dayton, Ohio. Over the last three years of reports there has been illicit gabapentin use in seven of eight urban regions in Ohio. See Table 1 in the OSAM bulletin for more information.

Preliminary analysis of OSAM’s most recent data for July to December 2016, found street availability and illicit use of Neurontin® to be moderate to high in six of the eight OSAM regions. In Athens, a participant commented, “It seems like everyone is on Neurontin®.” A law enforcement officer noted, “Enormous Neurontin® abuse right now.”

Gabapentin, known by its brand name of Neurontin®, is an anticonvulsant medication approved by the FDA as adjunctive treatment of partial seizures and to manage neuropathic pain from shingles. It has a variety of touted off label uses, and was referred to as “the snake oil of the 20th century” in an internal Pfizer email.  It is currently seen as having a low abuse profile and is not scheduled as a controlled substance by the DEA. But that may need changing.

It is also used to by opioid users to self-medicate through withdrawal and as a high in itself. One individual in Ohio said his attraction to Neurontin® was that it intensified his methadone: “So if you take your methadone and you go buy 10 Neurontin® and you take all 10, it’s sort of like you tripled your dose.” Others said they get a “semi-euphoric feeling” if they abuse it. Some recent studies: “Abuse and Misuse of Pregabalin and Gabapentin” and “Gabapentin Misuse, Abuse and Diversion: a Systematic Review” said gabapentin is most often abused by individuals with a history of drug abuse, especially opioids. And it is “being misused internationally.”

An article in Pharmacy Times indicated the number of prescriptions written for gabapentin was at an all time high. “According to a report by IMS Health, 57 million prescriptions for gabapentin were written in the United States in 2015, a 42% increase since 2011.” Alone it has a low abuse potential, but when combined with muscle relaxants, opioids of anxiety medications “gabapentin’s potential for abuse and addiction significantly increasing and ultimately gets those individuals high.” A study of Florida inmates found it was being crushed and snorted like cocaine. “Out of 96 prescriptions, only 19 were actually in the hands of an inmate that was actually prescribed that drug.”

An article in Pain News Network noted a study of urine samples from patients being treated at pain clinics found that 22% (70 out of 323) were taking gabapentin without a prescription. Researchers found of those patients taking gabapentin illicitly, 56% were taking it with an opioid; 27% with an opioid and a muscle relaxant or anxiety medications like benzodiazepines. The medical director of ARIA Diagnostics in Indianapolis, Indiana said the high rate of misuse was surprising as well as a wake up call for prescribers. Doctors don’t usually screen for gabapentin abuse when making sure patients are taking medications as prescribed.

Little information exists regarding the significance of Gabapentin abuse among clinical patients. Until recently, it was considered to have little potential for abuse however this review has shown that a significant amount of patients are taking Gabapentin without physician consent. This could be due to the fact that recent studies have revealed that Gabapentin may potentiate the ‘high’ obtained from other central nervous system acting drugs.

In the UK, gabapentin and pregabalin (Lyrica) prescribing is getting scrutinized more closely. At least 38 deaths involving pregabalin and 26 involving gabapentin were reported in the UK between 2012 and the end of 2015. The UK Advisory Council on the Misuse of Drugs (ACDMD) recommended they be reclassified as Class C controlled substances. “Both pregabalin and gabapentin are increasingly being reported as possessing a potential for misuse. When used in combination with other depressants, they can cause drowsiness, sedation, respiratory failure and death.”

Pregabalin may have a higher abuse potential than gabapentin because of its rapid absorption, faster onset of action and higher potency. It also causes a high or elevated mood in users. The side effects can include chest pain, wheezing, changes in vision and less frequently, hallucinations, Gabapentin was said to produce feelings of relaxation, calmness and euphoria. If snorted, its high is similar to using a stimulant.

The use of gabapentin and pregabalin by the opioid abusing population either together or when opioids are unavailable reinforces the behavior patterns of this high-risk population. There is a high risk of criminal behavior stimulated by the wish to obtain gabapentin and pregabalin.

Lyrica (pregabalin) is Pfizer’s top selling drug, with $6 billion in 2014 sales. Pfizer said reclassifying its drugs could harm patients. “Controlling the supply of these products across the whole UK, would be a disproportionate measure that would impact on patients and their quality of life.” An Irish study found pregabalin abuse a “serious emerging problem.” Recreational users in Belfast call the drug “Budweisers because it induces a state similar to drunkenness.” Gabapentin has received more attention as a potential drug of abuse in the US.

In 2012, “Has Gabapentin Become a Drug of Abuse?” appeared in Medscape, but the problem seems to have been somewhat downplayed. The article said: “a small number of postmarketing cases report gabapentin misuse and abuse,” but went on to say the rationale for abuse was unknown. Yet one of cited references for the Medscape article, “Abuse, dependency and withdrawal with gabapentin: a first case report,” did note that consumer websites reported several experiences of gabapentin misuse in order to feel high. “According to these consumer reports, gabapentin effects are close to those of marijuana and can appear with low doses.” Then the article reviewed several articles noting problems with abuse, misuse and withdrawal with gabapentin, essentially what has been reported above. In its conclusion, the article said:

 On the basis of case reports and postmarketing reports, there appears to be potential for abuse, dependency, and withdrawal symptoms associated with gabapentin use. Patients involved in this misuse and abuse were using gabapentin at doses greater than those recommended, to relieve symptoms of withdrawal from other substances, and for uses that are not FDA-approved.Providers should assess patients for drug abuse history when prescribing gabapentin, as well as monitor patients for any signs of misuse or abuse. Prescribers and pharmacists should monitor patients for the development of tolerance, unauthorized escalation of dosing, and requests for early refills or other aberrant behavior. Prescribers should consider requesting testing for the presence of gabapentin in urine drug screens if abuse is suspected.

I’ve personally been hearing reports from individuals in treatment for opioid drug problems consistent with the above information for several years. On one occasion, a woman said after she had told a psychiatrist she has a history of abusing gabapentin, but he prescribed it to her anyway. If you’re interested, a previous article I wrote, “Twentieth Century Snake Oil” reviews a history of Neurontin (gabapentin) that may surprise you. Another article, “The Dark Side of a Pill to Cure Addiction” reviewed mixed findings when gabapentin was used to treat alcohol withdrawal.