Baclofen and γ-Hydroxybutyrate (GHB), a Dangerous Combination

Non-medical use of baclofen: A case series and review of the literature

BACKGROUND

Baclofen is widely used for spastic disorders and, most recently, for addictive disorders. The first signals of baclofen abuse occurred in the last decade. This study aims to assess the motives, diversion sources, and routes of administration associated with the non-medical use of baclofen and examine health problems related to the non-medical use of baclofen.

METHODS

Spontaneous reports of baclofen abuse reported to the addictovigilance centre of East France were analysed. A literature search was conducted using PubMed®, Web of Sciences®, and Google Scholar® databases. Both investigations were performed in February 2021 without a time limit.

RESULTS

Forty-six cases were analysed (33 from the literature review and 13 from the addictovigilance base). Baclofen's non-medical use mainly affected male subjects with addictive history, but issues of primary abuse in subjects without any substance abuse history were also observed. Euphoria search was the most common reason for misuse. The route of administration included oral, snorting, and sublingual use. Some cases involving illegal sources were also observed. Most patients misusing baclofen presented severe complications, mainly represented by neurological and respiratory disturbances. Physical and psychological dependence on baclofen was observed in three persons.

CONCLUSIONS

Although baclofen abuse remains relatively infrequent or (most likely) underestimated, this study helped confirm baclofen's intrinsic abuse potential and make visible the baclofen-abuse-related health visible harms. Careful consideration and benefit-risk analysis should be employed when prescribing baclofen, and emergency departments should be aware of baclofen dangers in abuse situations.

Clinical Presentations and Treatment of Phenibut Toxicity and Withdrawal: A Systematic Literature Review

OBJECTIVES

This systematic review aimed to identify published articles that evaluated all phenibut toxicity and withdrawal cases to understand better their clinical presentations and treatments.

METHODS

A comprehensive literature search was conducted using Medline (Ovid), Embase (Ovid), and Cochrane Library databases to capture all published cases on the presentations and management of phenibut toxicity or withdrawal.

RESULTS

Sixty-two cases from 36 studies on presentation and management of phenibut toxicity or phenibut withdrawal were identified. Of all subjects, 80.7% were male. The average age was 30.9 years (SD, 13.2 years; range, 0-71 years). A total of 86.8% reported obtaining phenibut online, and 63.2% reported concomitant substance use with other addictive agents; benzodiazepines and alcohol were the most combined drugs. The average length of hospital stay was 5.0 days (n = 25; SD, 5.4 days; range, 1-25 days) for phenibut toxicity and 7.7 days (n = 20; SD, 7.8 days; range, 0-30 days) for phenibut withdrawals. The most common symptoms reported during phenibut toxicity were altered mental status, somnolence, psychosis, and movement disorders. Of the phenibut toxicity cases, 48.7% required intubation. Benzodiazepines and antipsychotics were most used to treat phenibut toxicity. For phenibut withdrawal cases, 95.7% reported daily use. The most common symptoms reported during phenibut withdrawals were anxiety, irritability or agitation, insomnia, and psychosis. Sixteen (69.6%) of phenibut withdrawal cases required multiple medications for treatment. Benzodiazepines, baclofen, atypical antipsychotics, gabapentanoids, and barbiturates were commonly used to treat phenibut withdrawals.

CONCLUSIONS

The seriousness of presentations, combined with the assortments of medications used for both syndromes, reflects the potential dangers of phenibut use and the need for systematized treatment protocols.

Baclofen: To Screen or Not to Screen in Postmortem Blood?

Baclofen (BLF) has been prescribed in the UK since 1972 for the alleviation of spasticity. However, evidence suggests BLF is also recreationally misused. It has been associated with ethanol, gamma-hydroxybutyric acid (GHB), pregabalin (PGL) and gabapentin (GBP) use/abuse, and deaths have been reported. With current postmortem (PM) toxicological screening approaches, BLF is not routinely included in the general drugs screen and is only screened for if specifically mentioned in the case documents. The extent of BLF misuse is thus unclear. This study was carried out to determine the prevalence and concentrations of BLF in Coroners' toxicology, to investigate whether BLF misuse with ethanol, GHB, PGL and GBP is causing death and to determine the potential extent of the underreporting of BLF-associated deaths. Between 1 January 2016 and 31 December 2017, 3,750 PM femoral vein bloods were screened for BLF; all positive cases were quantified. Only 0.56% of samples screened positive for BLF, with concentration ranging from 0.08 to 102.00 µg/mL (median = 0.28). It was determined that if routine analysis without additional screening of BLF had been performed, 43% of BLF positives cases would have been missed. However, given the low incidence of detection, this only represents 0.25% of the cohort. Likely illicit use of BLF with GHB was seen in one case only. Death from the recreational use of BLF with PGL and GBP was not observed. Only two cases positive for BLF had an ethanol concentration of ≥50 mg%. Two cases of presumed intentional overdose of BLF were observed. This study highlights that although BLF abuse may be occurring, deaths are rare. It is therefore not cost- or time-effective to screen for BLF in all PM cases. With BLF currently being investigated for the treatment of alcoholism and withdrawal symptoms of illicit drug use, BLF-related deaths may rise in the future.

Safety and Tolerability of the Anxiolytic and Nootropic Drug Phenibut: A Systematic Review of Clinical Trials and Case Reports

Phenibut is a nootropic drug that exerts anxiolytic and antinociceptive effects by acting on the GABA_B receptor and the α₂-δ subunit of voltage-dependent calcium channels. An increased number of reports of dependence to and intoxication by phenibut purchased online on the one hand and the wide prescription of phenibut in Eastern Europe for more than half a century on the other hand have resulted in a number of controversies regarding its use. In this review, we have summarized currently available information from case reports of phenibut dependence and intoxication and safety data from clinical trials. We included 14 dependence and intoxication case reports (16 patients) and reviewed 11 phenibut clinical trials (583 patients). The clinical symptoms in the case reports included cardiovascular effects, insomnia, anxiety and agitation, hallucinations, and depressed level of consciousness. In addition, the doses used (0.5-100 g/day) were much higher than the recommended daily dose (0.25-2 g/day). An analysis of phenibut side effects described in the clinical trials showed adverse events in only 5.66% of patients, and the most reported side effect was somnolence (1.89%). There are discrepancies in the reported side effects of phenibut in clinical trials compared to those reported in cases of online-purchased phenibut dependence and intoxication. The current systematic review provides evidence that, at therapeutic doses, phenibut is safe and well tolerated with minor adverse effects, but questions regarding the quality of phenibut obtained online and the contribution of alcohol and other drug abuse to phenibut dependence and intoxication remain open.

DARK Classics in Chemical Neuroscience: Gamma-Hydroxybutyrate (GHB)

Gamma-hydroxybutyrate (GHB) is a naturally occurring short-chain fatty acid that rose to prominence as a popular club drug in the 1990s. Originally developed as an anesthetic in the early 1960s, it was later sold as an over-the-counter dietary supplement before becoming a rising substance of abuse in the following decades as one of the "date rape" drugs. Despite its abuse potential, there has been a recent surge in therapeutic interest in the drug due to its clinical viability in the treatment of narcolepsy and alcohol abuse/withdrawal. Its interactions with the GABAergic framework of higher mammals has made it the prototypical example for the study of the chief inhibitory mechanism in the human central nervous system. Though relatively obscure in terms of popular culture, it has a storied history with widespread usage in therapeutic, recreational ("Chemsex"), and some disturbingly nefarious contexts. This Review aims to capture its legacy through review of the history, synthesis, pharmacology, drug metabolism, and societal impact of this DARK classic in chemical neuroscience.

Baclofen in gamma-hydroxybutyrate withdrawal: patterns of use and online availability

Purpose

Gamma-hydroxybutyrate (GHB) withdrawal is a life-threatening condition that does not always respond to standard treatment with benzodiazepines. Baclofen has potential utility as a pharmacological adjunct and anecdotal reports suggest that it is being used by drug users to self-manage GHB withdrawal symptoms. Here, we investigate current patterns of use and the online availably of baclofen.

Methods

Data triangulation techniques were applied to published scientific literature and publicly accessible Internet resources (grey literature) to assess the use of baclofen in GHB withdrawal. An Internet snapshot survey was performed to identify the availability of baclofen for online purchase and the compliance of retailers with the UK regulations. Data were collected according to pre-defined criteria.

Results

A total of 37 cases of baclofen use in GHB withdrawal were identified in the scientific literature, as well as 51 relevant discussion threads across eight Internet forums in the grey literature. Baclofen was available to purchase from 38 online pharmacies, of which only one conformed to the UK regulations.

Conclusions

There is limited published evidence on the use of baclofen in GHB withdrawal, but both scientific and grey literature suggests clinical utility. Online pharmacies are readily offering prescription-only-medication without prescription and due to inadequate regulation, pose a danger to the public.

Electronic supplementary material

The online version of this article (10.1007/s00228-017-2387-z) contains supplementary material, which is available to authorized users.

Detoxification with titration and tapering in gamma-hydroxybutyrate (GHB) dependent patients: The Dutch GHB monitor project

BACKGROUND AND AIMS

Gamma-hydroxybutyrate (GHB) detoxification procedures have been insufficiently studied for effectiveness and safety. Based on case reports, benzodiazepines are generally regarded as first-choice agents in GHB detoxification. Detoxification by titration and tapering (DeTiTap) with pharmaceutical GHB in an open-label consecutive case series of 23 GHB-dependent patients showed to be feasible, effective and safe. This study further explored the feasibility, effectiveness and safety of this detoxification procedure in a large group of patients.

METHOD

A large observational multicenter study was carried out in six addiction treatment centers in the Netherlands. GHB-dependent inpatients (229 unique patients, 274 admissions) were titrated on and tapered off with pharmaceutical GHB.

RESULTS

Successful detoxification was achieved in 85% of cases. Detoxification was carried out in 12.5days in most patients. The DeTiTap procedure proved to be feasible and significantly reduced the experienced withdrawal symptoms and craving (p≤0.001). Several symptoms were found to influence the course of subjective withdrawal symptoms. During detoxification, psychological symptoms such as depression, anxiety, and stress decreased (p≤0.05). The main complications were hypertension and anxiety. Six patients were sent to the general hospital for observation, but all six were able to continue detoxification in the addiction treatment centers. Most patients (69%) relapsed within three months after detoxification.

CONCLUSIONS

The DeTiTap procedure using pharmaceutical GHB seems a safe alternative to benzodiazepines as a GHB detoxification procedure. However, the high relapse rates warrant further investigation.

An Unusual Case of Baclofen Abuse

Baclofen was initially used for the treatment of spastic conditions. Last decade has seen its emergence as a treatment of profound interest in alcohol dependence, opiates and cocaine abuse, and tobacco addiction. However, the published literature on baclofen abuse is sparse. Here, we report a patient with baclofen abuse.

Baclofen as relapse prevention in the treatment of gamma-hydroxybutyrate dependence: a case series

In the last decade, gamma-hydroxybutyrate (GHB) abuse and dependence have increased. It has been reported that GHB dependence has a high rate of relapse, serious complications of intoxication, and a potentially life-threatening withdrawal syndrome. Nevertheless, in clinical practice, there is no known medical treatment to support GHB relapse prevention. We describe a case series of patients who were supported through an off-label treatment with baclofen to avoid a relapse into GHB abuse, for a period of 12 weeks. Nine of 11 patients did not relapse while taking a dose ranging from 30 to 60 mg per day, one patient relapsed after 5 weeks, and one stopped after 7 weeks. Baclofen was well tolerated; patients reported mild side effects such as fatigue, nausea, dry mouth, excessive sweating, and depressive feelings. Although systematic evidence is still lacking, our practice-based experience suggests that treatment with baclofen to assist abstinence might be effective in patients with GHB dependence. Further systematic controlled studies are necessary to establish the exact efficacy and safety of baclofen as relapse prevention for GHB-dependent patients.