Pharmacological treatment of alcoholism

Mother's little helper turned a foe: Alprazolam use, misuse, and abuse

Benzodiazepines are effective in managing anxiety and related disorders when used properly (short-term). Their inappropriate use, however, carries significant risks, involving amnesia, rebound insomnia, rebound anxiety, depression, dependence, abuse, addiction, and an intense and exceedingly prolonged withdrawal, among other complications. Benzodiazepines also amplify the effects of opioids and, consequently, have been implicated in approximately 30 % of opioid overdose deaths. Despite their unfavorable profile, sharp increases in medical and non-medical use of benzodiazepines have been steadily reported worldwide. Alprazolam (Xanax®), a potent, short-acting benzodiazepine, is among the most prescribed and abused anxiolytics in the United States. This medication is commonly co-abused with opioids, increasing the likelihood for oversedation, overdose, and death. Notwithstanding these risks, it is surprising that research investigating how benzodiazepines, such as alprazolam, interact with opioids is severely lacking in clinical and preclinical settings. This review therefore aims to present our current knowledge of benzodiazepine use and misuse, with an emphasis on alprazolam when data is available, and particularly in populations at higher risk for developing substance use disorders. Additionally, the potential mechanism(s) surrounding tolerance, dependence and abuse liability are discussed. Despite their popularity, our understanding of how benzodiazepines and opioids interact is less than adequate. Therefore, it is now more important than ever to understand the short- and long-term consequences of benzodiazepine/alprazolam use.

Berberine protects C57BL/6J mice against ethanol withdrawal-induced hyperexcitability

Berberine ([C20H18NO4](+) ), one of the major constituents of the Chinese herb Rhizoma coptidis, is an isoquinoline alkaloid. Plethora of recent reports has indicated its ability to modulate several neurotransmitter systems, especially those implicated in ethanol dependence. Thus, the influence of berberine treatment on the development and expression of ethanol dependence was tested by using the ethanol withdrawal-induced hyperexcitability paradigm. Mice were provided with a nutritionally balanced control liquid diet as the sole nutrient source on day 0; from day 1-4 (ethanol, 3% v/v), from day 5-7 (ethanol, 6% v/v) and from day 8-10 (ethanol, 10% v/v) was incorporated into the liquid diet. On day 11, the ethanol liquid diet was replaced with nutritionally balanced control liquid diet, and ethanol withdrawal-induced hyperexcitability signs were recorded. The results revealed that acute administration of berberine (10 and 20 mg/kg, i.p.) dose-dependently attenuated ethanol withdrawal-induced hyperexcitability signs, and these results were comparable to diazepam (1.25 and 2.5 mg/kg, i.p.). Further, chronic administration of berberine (10 and 20 mg/kg, i.p.) to the ethanol diet fed mice markedly attenuated the ethanol withdrawal-induced hyperexcitability signs. In conclusion, the results and evidence suggest that berberine exhibited an inhibitory influence against ethanol withdrawal-induced hyperexcitability signs, which could be mediated through its neuromodulatory action.

Inhibitory influence of mecamylamine on ethanol withdrawal-induced symptoms in C57BL/6J mice

Several reports show the involvement of neuronal nicotinic acetylcholine receptors (nAChRs) in the behavioral effects of ethanol, including ethanol drinking and relapse. Therefore, this study evaluated the effects of mecamylamine, a nAChR antagonist, on ethanol withdrawal signs. Ethanol dependence was induced in C57BL/6J mice by ethanol liquid diet administration. Animals were provided with nutritionally balanced control liquid diet (600 kcal/l) as their sole nutrient source on day 0; from days 1 to 4, 3% v/v of ethanol, followed by 6% v/v of ethanol (from days 5 to 7), and 10% v/v of ethanol (from days 8 to 10) were incorporated into the liquid diet. On day 11, ethanol liquid diet was replaced with nutritionally balanced control liquid diet, and ethanol withdrawal-induced physical signs were recorded. Results showed that acute administration of mecamylamine (1-4 mg/kg, intraperitoneally) dose-dependently attenuated ethanol withdrawal-induced signs, and these effects were comparable with those of diazepam (1-2 mg/kg, intraperitoneally). In addition, chronic administration of mecamylamine into ethanol diet-fed mice markedly attenuated the ethanol withdrawal sign scores, thus supporting the contention that nAChR is involved in ethanol dependence. In conclusion, our results suggest that mecamylamine exhibited inhibitory effects on ethanol withdrawal signs which could be mediated through nAChR.

The anxiolytic etifoxine protects against convulsant and anxiogenic aspects of the alcohol withdrawal syndrome in mice

Change in the function of gamma-aminobutyric acid(A) (GABA(A)) receptors attributable to alterations in receptor subunit composition is one of main molecular mechanisms with those affecting the glutamatergic system which accompany prolonged alcohol (ethanol) intake. These changes explain in part the central nervous system hyperexcitability consequently to ethanol administration cessation. Hyperexcitability associated with ethanol withdrawal is expressed by physical signs, such as tremors, convulsions, and heightened anxiety in animal models as well as in humans. The present work investigated the effects of anxiolytic compound etifoxine on ethanol-withdrawal paradigms in a mouse model. The benzodiazepine diazepam was chosen as reference compound. Ethanol was given to NMRI mice by a liquid diet at 3% for 8 days, then at 4% for 7 days. Under these conditions, ethanol blood level ranged between 0.5 and 2 g/L for a daily ethanol intake varying from 24 to 30 g/kg. These parameters permitted the emergence of ethanol-withdrawal symptoms once ethanol administration was terminated. Etifoxine (12.5-25 mg/kg) and diazepam (1-4 mg/kg) injected intraperitoneally 3h 30 min after ethanol removal, decreased the severity in handling-induced tremors and convulsions in the period of 4-6h after withdrawal from chronic ethanol treatment. In addition when administered at 30 and 15 min, respectively, before the light and dark box test, etifoxine (50mg/kg) and diazepam (1mg/kg) inhibited enhanced aversive response 8h after ethanol withdrawal. Etifoxine at 25 and 50 mg/kg doses was without effects on spontaneous locomotor activity and did not exhibit ataxic effects on the rota rod in animals not treated with ethanol. These findings demonstrate that the GABAergic compound etifoxine selectively reduces the physical signs and anxiety-like behavior associated with ethanol withdrawal in a mouse model and may hold promise in the treatment of ethanol-withdrawal syndrome in humans.

Participation of alpha-melanocyte stimulating hormone in ethanol-induced anxiolysis and withdrawal anxiety in rats

Although recent reports underscore a close association between the ethanol consumption and the central melanocortin (MC) system in rats, neurobehavioral component of this association has not been explored. In this study, we investigated the role of alpha-melanocyte stimulating hormone (alpha-MSH) in ethanol (1.5-2 g/kg, i.p.) induced anxiolysis and anxiety-like behavior following withdrawal from prolonged ethanol (9% v/v ethanol, 15 days) consumption, using elevated plus maze (EPM) test in rats. While alpha-MSH (1-5 microg/rat, i.c.v.) showed dose-dependent anxiogenic-like effect, the MC4 receptor antagonist HS014 (1-10 nM/rat, i.c.v.) or antiserum against alpha-MSH (1:500-1:50 dilution, 5 microl/rat, i.c.v.) failed to produce any effect in the EPM test. The anxiolytic-like effect of ethanol was suppressed by central administration of alpha-MSH (0.5 microg/rat, i.c.v.). On the other hand, pretreatment with either HS014 (5 nM/rat, i.c.v.) or antiserum against alpha-MSH (1:100 dilution, 5 microl/rat, i.c.v.) enhanced anxiolytic action of ethanol. Moreover, ethanol withdrawal anxiety was markedly blocked by HS014 (1-10 nM/rat, i.c.v.). These results suggest that alpha-MSH may be implicated in ethanol-induced anxiolysis and withdrawal anxiety. These findings also suggest MC4 receptors as possible therapeutic target for development of drugs to address the ethanol withdrawal-related conditions.

Drug interactions between psychoactive substances and antiretroviral therapy in individuals infected with human immunodeficiency and hepatitis viruses

The liver disease characteristic of alcohol dependence encompasses three main related entities: steatosis, alcoholic hepatitis, and cirrhosis. Alcoholic cirrhosis is a leading cause of global morbidity and mortality. Alcohol intake among injecting drug users is a major contributor to transmission of viral infections, such as human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C viruses (HCV). HIV and HCV coinfected patients develop liver diseases earlier and more severely than the monoinfected individuals, including hepatocellular carcinoma. Interactions exist between the therapeutic drugs used to minimize and control the drug and alcohol dependence. Furthermore, drug-drug interactions occur between the highly active antiretroviral therapy (HAART) and alcohol, different HAART components and methadone, or each one of the therapies with the other, thus contributing to a higher toxicity level. With the evolution of effective antiretroviral therapy, survival of persons with HIV, and the syndrome it causes, acquired immunodeficiency syndrome (AIDS) has increased dramatically. Drug-drug interactions may appear between alcohol and anti-HBV or anti-HCV, therapy in the presence or absence of anti-HIV therapy. Several other medical-, social-, and drug-related factors of this population have to be considered when providing HAART. Because many coinfected patients also have problems with substance use, dealing with their drug dependence is an important first step in an attempt to improve adherence to and tolerance of antiviral therapy. It is necessary to minimize the risk of liver disease acceleration and/or reinfection with hepatitis viruses. Knowledge of potential drug interactions between methadone, antiretroviral therapy, psychoactive drugs, and antipsychotics and the role of coinfection with HBV or HCV and the drugs used in eradicating viral hepatitis permits suitable antiretroviral combinations.

Double-blind study of cyamemazine and diazepam in the alcohol withdrawal syndrome

OBJECTIVE

Cyamemazine is an original phenothiazine derivative which showed similar efficacy and tolerability to lorazepam during ethanol withdrawal in mice. This study investigated cyamemazine for its efficacy and tolerability in alcohol-dependent patients electing an alcohol withdrawal procedure, in comparison with diazepam.

METHOD

A multicenter, randomized, double-blind study in 89 alcohol-dependent patients (CIWA-Ar score between 10 and 30), electing an alcohol withdrawal procedure, was used to find effective doses of cyamemazine and to compare it with diazepam for efficacy and tolerability. On day 1 (D(1)), cyamemazine or diazepam (50 mg and 10 mg capsule, respectively) were administered at hourly intervals to reduce CIWA-Ar = 5, up to a maximum of eight administrations. Starting from D(2), the compounds were given twice a day in progressively decreasing doses during a maximum period of 13 days (D(end)).

RESULTS

At h(8) (8 h after the first treatment of D(1)), therapeutic success (CIWA-Ar score </= 5) was achieved in 32 out of 43 ITT patients treated with cyamemazine (74.4%), a value very similar to that of diazepam (32/44; 72.7%). Most such patients (29/32) were controlled with 2-6 capsules of cyamemazine (100-300 mg). In the PP population, cyamemazine (n = 28) was significantly non-inferior to diazepam (n = 33), with a threshold of 10% for non-inferiority bound and 2.5% for one-sided type I error rate. Such therapeutic similarity was confirmed by the analysis of other efficacy criteria. Safety analysis did not show substantial differences between the two treatments.

CONCLUSIONS

Cyamemazine showed similar efficacy and tolerability to diazepam for the treatment of alcohol withdrawal symptoms at therapeutic doses in the range 100-300 mg.

A fatal clomipramine intoxication case of a chronic alcoholic patient: Application of postmortem hair analysis method of clomipramine and ethyl glucuronide using LC/APCI/MS

Toxicological investigations of postmortem specimens of a 26-year-old man were performed with the use of LC/APCI/MS. They revealed in the blood of the deceased clomipramine (9.49 microg/g) and its main metabolite norclomipramine (1.10 microg/g) at concentrations explaining the fatal outcome. The presence of these xenobiotics in a 12-cm-long strand of hair (clomipramine, 7.60 ng/mg in I segment; 4.19 ng/mg in II segment; 1.86 ng/mg in III segment; norclomipramine, 5.71 ng/mg in I segment; 9.71 ng/mg in II segment; 4.13 ng/mg in III segment) confirmed the fact obtained from the medical history that the deceased had been receiving clomipramine as an antidepressant for 1 year prior to his death. The analysis demonstrated ethanol in autopsy blood (2.5mg/ml) and urine (3.2mg/ml); ethyl glucuronide as a marker of chronic alcohol abuse was detected in the deceased's hair (0.44 ng/mg in I segment; 0.07 ng/mg in II segment; n.d. in III segment). These findings may suggest the contribution of alcohol in the mechanism of drug-ethanol interaction, which in consequence might have affected the biotransformation of clomipramine in the final period of his life and evoked the ultimate toxic effect.

The Dopamine D1 Antagonist Reduces Ethanol Reward for C57BL/6 Mice

BACKGROUND

Dopamine D1 antagonist effects on behaviors related to obtaining and consuming ethanol remain unclear. The highly selective D1 antagonist ecopipam (SCH 39166), which has no effect on the serotonin system, was used to evaluate the role of D1 receptors in ethanol reward and its potential for treating alcohol abuse by determining its effect on several measures of ethanol reward in C57BL/6 (B6) mice.

METHODS

Ecopipam (0.025-0.2 mg/kg) effects on instrumental and contingent consummatory responses and on noncontingent consummatory responses for ethanol and water reward were determined in food-restricted male mice trained to lever-respond for 12% ethanol delivered on a fixed ratio-4 reinforcement schedule. The mice were tested for 15-min sessions under preprandial (high-hunger and low-thirst) and postprandial (low-hunger and high-thirst) test conditions.

RESULTS

Ecopipam dose-dependently reduced instrumental and consummatory responses for ethanol and ethanol intake when tested under hunger- or thirst-motivated conditions with free access to water. Under thirst motivation with no access to an alternate fluid source, lever responses for ethanol and water were similar; however, ecopipam reduced responding for ethanol more than responding for water reward. When given concurrent free access to the same fluid delivered for lever pressing, animals made more contacts for ethanol than for water; ecopipam reduced free ethanol but not water contacts.

CONCLUSIONS

Ecopipam attenuated ethanol reward at doses that did not affect water reward, indicating an effect independent of reductions in motor system function or general motivation and arousal. Ecopipam also reduced ethanol reward to the same degree under hunger, thirst, or sated conditions, again indicating that it affected ethanol reward at doses that did not grossly affect general motivational states. These data suggest that ecopipam may reduce ethanol reward with few side effects and that it warrants further investigation as a pharmacological tool for treating alcohol abuse.

Role of protein kinase C in estrogen protection against apoptotic cerebellar cell death in ethanol-withdrawn rats

Results of studies from our laboratory have shown that administration of 17beta-estradiol (E(2)) reduces cerebellar neuronal damage during ethanol withdrawal (EW). In the current study, we examined mechanisms underlying E(2) protection against EW-associated cerebellar damage by assessing apoptotic indicators: DNA fragmentation, caspase-3 activity, and protein kinase C (PKC) activity. Ovariectomized rats, implanted with E(2) or oil pellets, received ethanol [7.5% weight/volume (wt./vol.)] (EW/E(2) group and EW/Oil group, respectively) chronically (for 5 weeks) or control dextrin diet (Dextrin/Oil group). At day 14 of EW, cerebelli were collected for the terminal deoxynucleotidyltransferase (TdT)-mediated dUDP-biotin nick end labeling (TUNEL) assay to detect DNA fragmentation and for immunohistochemistry to detect caspase-3 activation. A separate group of rat cerebelli was prepared to assess for total PKC activity, as well as for activity of a specific PKC isozyme, epsilon (PKCepsilon), by using an in vitro [gamma-(32)P]ATP phosphorylation assay at days 1 and 14 of EW. Results indicated that rats in the EW/Oil group had more DNA fragments and caspase-3-positive neuronal cells than observed for control rats, and these effects were inhibited by E(2) treatment. For total PKC activity at day 1 of EW, rats in the EW/E(2) group had a lower cytosolic PKC activity than observed for either rats in the EW/Oil group or control rats. At day 14 of EW, both EW groups had a lower total PKC activity than observed for control rats. For PKCepsilon activity, rats in the EW/E(2) group had a lower cytosolic PKCepsilon activity than observed for rats in the EW/Oil group or for control rats at day 1, and they had a lower membrane PKCepsilon activity at day 14 of EW than observed for control rats. These findings support the suggestion that E(2) protects against cerebellar neuronal damage in ethanol-withdrawn rats by inhibition of DNA fragmentation and caspase-3 activation, and that reduced PKC activity may be involved in the protection.

Role of the GABAA system in behavioral, motoric, and cerebellar protection by estrogen during ethanol withdrawal

Results of studies from our laboratory have shown that administration of 17beta-estradiol (E(2)) reduces cerebellar neuronal damage during ethanol withdrawal (EW). In the current study, we investigated whether the GABAergic system is involved in the protective effects of E(2) against the EW syndrome. To test this hypothesis, we examined the effects of GABAergic drugs, with and without E(2), on EW sign scores, motoric capacity, and caspase activation. Ovariectomized rats implanted with an E(2) or an oil pellet received liquid ethanol [7.5% weight/volume (wt./vol.)] for 5 weeks or dextrin diet, followed by 2 weeks of EW. A gamma-aminobutyric acid type A (GABA(A)) agonist, muscimol (0.125 or 0.25 mg/kg), and antagonist, bicuculline (1.25 mg/kg), were administered (intraperitoneally; three times a day for 4 days) starting 1 day before the onset of EW. On termination of chronic administration of ethanol diet, rats were tested for overt withdrawal signs and latency to fall from a rotarod. The initial latency was measured separately to assess motoric capacity before learning occurred. Cerebelli were subsequently collected for immunohistochemistry to detect caspase activation. Results showed that treatment with E(2) lowered EW sign scores and improved initial as well as subsequent rotarod latencies compared with findings without treatment with E(2) (control group). These effects of E(2) were enhanced by combined treatment with muscimol and diminished by bicuculline. Results also showed that ethanol-withdrawn rats had more caspase-3-positive cells than observed for the dextrin diet-fed group in a manner reversed by E(2) and exacerbated by bicuculline. Bicuculline also caused partial antagonism of the protective effect of E(2). These findings support the suggestion that GABA(A) agonists ameliorate, and GABA(A) antagonists exacerbate, EW signs, cerebellar neuronal damage, and motoric impairment in ethanol-withdrawn rats. Also, results of the current study provide indirect evidence that the GABAergic system is involved in protective effects of E(2) against the EW syndrome.

Estradiol protects against cerebellar damage and motor deficit in ethanol-withdrawn rats

On the basis of findings obtained from this study, we hypothesize that the female sex steroid 17beta-estradiol (E(2)) protects against cerebellar neuronal damage and behavioral deficit in rats withdrawn from chronic ethanol exposure. Ovariectomized rats implanted with E(2) or an oil pellet received liquid ethanol (7.5% [wt./vol.]) or dextrin diet for 5 weeks, followed by 2 weeks of ethanol withdrawal. On termination of diet administration, rats were tested for both overt withdrawal signs and latency (seconds) to fall from an accelerating rotarod in six consecutive sessions (the longer the latency, the better the performance). The initial latency was measured separately to assess motoric capacity before learning occurred. Rats were then killed, and cerebella were prepared for accessing of Purkinje cell damage. The study revealed three specific findings. (1) In the absence of E(2), the ethanol withdrawal group showed higher total ethanol withdrawal sign scores than those for the dextrin group, whereas the score for the ethanol withdrawal group was lower in the presence of E(2). (2) In the absence of E(2), the ethanol withdrawal group showed shorter rotarod latency than that for the dextrin group, whereas the latency for the ethanol withdrawal group increased in the E(2)-treated group. In ethanol withdrawal groups, E(2) treatment also resulted in a longer latency than that observed with oil treatment in the initial session and in subsequent sessions. (3) Purkinje cell numbers in the ethanol withdrawal group without E(2) were lower than those in dextrin groups and in the ethanol withdrawal group with E(2) treatment. These findings support the suggestion that E(2) exerts protective effects against withdrawal signs, cerebellar neuronal damage, and motoric impairment in subjects exposed to, and withdrawn from, chronic ethanol exposure.

Management of Acute Alcohol Withdrawal in the Inpatient Setting

Collaborative drug therapy management (CDTM) is a method for developing a patient-centered practice in which the pharmacist's activities are integrated with those of other health care providers. The goals of this continuing feature are to refine the concept of CDTM and provide patient-care applications from the authors' experience in Washington state. Questions or suggestions should be addressed to Timothy S. Fuller, FASHP, Fuller and Associates, 1948 Boyer Avenue East, Seattle, WA 98112-2924 (tel.206-860-8308). E-mail: timfuller@kendra.com

Abecarnil and alprazolam reverse anxiety-like behaviors induced by ethanol withdrawal

This study investigated the effects of a benzodiazepine partial agonist, abecarnil, and a full agonist, alprazolam, on ethanol withdrawal-induced anxiety-like behaviors in rats. Anxiety was assessed in two models: elevated plus maze and pentylenetetrazol (GABA(A) antagonist) discrimination assay. Male rats received an ethanol-containing (4.5%) liquid diet for 7 to 10 days and were tested for withdrawal symptoms 12 h after termination of the diet. In the elevated plus maze, ethanol-withdrawn rats displayed less open arm activity and total arm entries than pair-fed rats. Abecarnil (0.08-0.32 mg/kg, IP) and alprazolam (0.08-1.25 mg/kg, IP) each produced a dose-dependent, full reversal of ethanol withdrawal-induced reduction of open arm activity, but only alprazolam increased the total arm entries. In the pentylenetetrazol assay, ethanol-withdrawn rats selected the pentylenetetrazol lever (100%) over the salin-lever. Abecarnil (0.04-0.32 mg/kg, IP) and alprazolam (0.08-0.32 mg/kg, IP) dose dependently reduced pentylenetetrazol-lever responding to control levels (10-20%). Alprazolam was more potent than abecarnil in reversing ethanol withdrawal-induced decrease in open arm activities, but showed comparable potency and efficacy to abecarnil in blocking the pentylenetetrazol-like ethanol withdrawal stimulus. These results suggest that abecarnil and alprazolam may have therapeutic potential for treatment of ethanol withdrawal-induced anxiety-like symptoms.

Current concepts in pharmacotherapy of substance abuse

The cost to society of alcohol, tobacco, and illicit drug dependence is enormous. Although the importance of treatment for substance abuse to public health is increasingly acknowledged, pharmacotherapy is generally underutilized. However, the selection of medications for clinical testing is increasingly guided by the rapidly evolving science of addictive drugs and behavior. The benefit of medication for smoking cessation is firmly established, particularly for nicotine replacement and antidepressant therapy. Naltrexone is an important addition to the pharmacopoeia, and acamprosate may soon be approved as well. Although no new medications are approved for cocaine and amphetamine abuse, a variety of candidate treatments have shown promise in ongoing studies. Opiate substitution therapy is highly effective for rehabilitation of heroin addiction, and several alternative forms will soon be available; alternative forms of opiate detoxification have also received attention. Overall, there is increasing recognition that physicians have an obligation to identify and treat all forms of substance dependence, although knowledge of the efficacy of the available treatments is steadily increasing.