Disulfiram-induced hepatitis. Report of four cases and review of the literature

Medications for alcohol use disorder promote abstinence in alcohol-associated cirrhosis: Results from a systematic review and meta-analysis

BACKGROUND AND AIMS

The role of medications for alcohol use disorder (MAUD) in patients with cirrhosis is not well established. Evidence on the efficacy and safety of these drugs in these patients is scarce.

APPROACH AND RESULTS

We performed a systematic review and meta-analysis according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocol guidelines on the efficacy of MAUD in patients with cirrhosis. A search was conducted in PubMed, Embase, and Scopus, including all studies until May 2022. The population was defined as patients with AUD and cirrhosis. The primary outcome was alcohol abstinence. Safety was a secondary outcome. We performed a random-effect analysis and expressed the results as relative risk of alcohol consumption. Heterogeneity was measured by I2 . Out of 4095 unique references, 8 studies on 4 different AUD treatments [baclofen (n = 6), metadoxine (n = 1), acamprosate (n = 1), and fecal microbiota transplant (n = 1)] in a total of 794 patients were included. Four were cohort studies, and 4 were RCTs. Only RCTs were included in the meta-analysis. MAUD was associated with a reduced rate of alcohol consumption [relative risk = 0.68 (CI: 0.48-0.97), P = 0.03], increasing alcohol abstinence by 32% compared to placebo or standard treatment, despite high heterogeneity ( I2 = 67%). Regarding safety, out of 165 serious adverse events in patients treated with MAUD, only 5 (3%) were possibly or probably related to study medications.

CONCLUSION

MAUD in patients with cirrhosis is effective in promoting alcohol abstinence and has a good safety profile. Larger studies on the effects of MAUD are needed, especially in patients with advanced liver disease.

Disulfiram: Mechanisms, Applications, and Challenges

Background: Since disulfiram’s discovery in the 1940s and its FDA approval for alcohol use disorder, other indications have been investigated. This review describes potential clinical applications, associated risks, and challenges. Methods: For this narrative review, a PubMed search was conducted for articles addressing in vivo studies of disulfiram with an emphasis on drug repurposing for the treatment of human diseases. The key search terms were “disulfiram” and “Antabuse”. Animal studies and in vitro studies highlighting important mechanisms and safety issues were also included. Results: In total, 196 sources addressing our research focus spanning 1948–2022 were selected for inclusion. In addition to alcohol use disorder, emerging data support a potential role for disulfiram in the treatment of other addictions (e.g., cocaine), infections (e.g., bacteria such as Staphylococcus aureus and Borrelia burgdorferi, viruses, parasites), inflammatory conditions, neurological diseases, and cancers. The side effects range from minor to life-threatening, with lower doses conveying less risk. Caution in human use is needed due to the considerable inter-subject variability in disulfiram pharmacokinetics. Conclusions: While disulfiram has promise as a “repurposed” agent in human disease, its risk profile is of concern. Animal studies and well-controlled clinical trials are needed to assess its safety and efficacy for non-alcohol-related indications.

Treating Alcohol Use Disorder in Patients with Alcohol-Associated Liver Disease: Controversies in Pharmacological Therapy

Alcohol use disorder (AUD) is one of the main causes of global death and disability. The liver represents the main target of alcohol damage, and alcohol-associated liver disease (ALD) represents the first cause of liver cirrhosis in Western countries. Alcohol abstinence is the main goal of treatment in AUD patients with ALD, as treatments for ALD are less effective when drinking continues. Moreover, the persistence of alcohol consumption is associated with higher mortality, increased need for liver transplantation, and graft loss. The most effective treatment for AUD is the combination of psychosocial interventions, pharmacological therapy, and medical management. However, the effectiveness of these treatments in patients with ALD is doubtful even because AUD patients with ALD are usually excluded from pharmacological trials due to concerns on liver safety. This narrative review will discuss the treatment options for AUD-ALD patients focusing on controversies in pharmacological therapy.

Recidivism in Liver Transplant Recipients for Alcohol-related Liver Disease

Liver transplantation (LT) is the only cure for patients with end-stage liver disease, which offers good long-term survival. The long-term issues after LT affecting survival are cardiovascular disease, chronic kidney disease, de novo malignancies, recurrence of original disease and immunological causes. Alcoholic-related liver disease (ALD) is one of the most common indications for LT worldwide including India. LT for ALD is associated with several unique challenges as compared with other etiologies. Long-term survival after LT in patients with ALD is affected by recidivism. Various studies have shown different predictors of relapse; the main predictors of relapse are pretransplant abstinence, psychiatric comorbidities, and lack of social support. Although several risk scores have been proposed, these scores are not validated. Studies with active involvement of psychiatrist have shown lower relapse rates. The relapse prevention strategy for reducing likelihood and severity of relapse after initial cessation of alcohol uses a combination of pharmacotherapy and cognitive behavioral approach (identifying and addressing high-risk situations for relapse).

Copper Ionophores as Novel Antiobesity Therapeutics

The therapeutic utility of the copper ionophore disulfiram was investigated in a diet-induced obesity mouse model (C57BL/6J background), both through administration in feed (0.05 to 1% (w/w)) and via oral gavage (150 mg/kg) for up to eight weeks. Mice were monitored for body weight, fat deposition (perigonadal fat pads), metabolic changes (e.g., glucose dyshomeostasis) and pathologies (e.g., hepatic steatosis, hyperglycaemia and hypertriglyceridemia) associated with a high-fat diet. Metal-related pharmacological effects across major organs and serums were investigated using inductively coupled plasma mass spectrometry (ICP-MS). Disulfiram treatments (all modes) augmented hepatic copper in mice, markedly moderated body weight and abolished the deleterious systemic changes associated with a high-fat diet. Likewise, another chemically distinct copper ionophore H2(gtsm), administered daily (oral gavage), also augmented hepatic copper and moderated mouse body weight. Postmortem histological examinations of the liver and other major organs, together with serum aminotransferases, supported the reported therapeutic safety of disulfiram. Disulfiram specifically altered systemic copper in mice and altered hepatic copper metabolism, perturbing the incorporation of copper into ceruloplasmin (holo-ceruloplasmin biosynthesis) and subsequently reducing serum copper concentrations. Serum ceruloplasmin represents a biomarker for disulfiram activity. Our results establish copper ionophores as a potential class of antiobesity agents.

Disulfiram-Induced Acute Liver Injury

Disulfiram is a drug used to treat alcohol dependence since many years. It interferes with the metabolism of alcohol, may be associated with neurological and dermatological symptoms, and can be hepatotoxic. Due to the frequent coexistent liver test alterations due to alcohol, the true incidence of disulfiram-associated liver injury is unclear and severity of injury may vary from mildly elevated liver enzymes to fulminant hepatitis leading to death. There are several reported cases of disulfiram hepatitis in the literature. Liver histology, when available, demonstrates some degree of portal inflammation with eosinophils and hepatocyte necrosis. We present here a well-documented case of acute hepatitis due to disulfiram with typical histological lesions, favorable outcome following drug withdrawal, and a brief steroid course. The risk of hepatotoxicity should be kept in mind when prescribing disulfiram.

Treating alcohol-related liver disease from a public health perspective

Herein, we describe the evolving landscape of alcohol-related liver disease (ALD) including the current global burden of disease and cost to working-aged people in terms of death and disability, in addition to the larger spectrum of alcohol-related heath complications and its wider impact on society. We further review the most effective and cost-effective public health policies at both a population and individual level. Currently, abstinence is the only effective treatment for ALD, and yet because the majority of ALD remains undetected in the community abstinence is initiated too late to prevent premature death in the majority of cases. We therefore hope that this review will help inform clinicians of the "public health treatment options" for ALD to encourage engagement with policy makers and promote community-based hepatology as a speciality, expanding our patient cohort to allow early detection, and thereby a reduction in the enormous morbidity and mortality associated with this disease.

National differences in disulfiram prescribing

Aims and method

To test the impression of wide national differences in the use of deterrent medication in the treatment of alcohol dependence, data showing comparative sales of disulfiram in 13 countries were obtained.

Results

Sales in Britain were lowest, and less than a tenth of those in Denmark. Rates bore no relation to alcohol sales or an index of alcohol-related problems in the 13 countries.

Clinical implications

British doctors may apply a particularly cautious risk/benefit ratio for disulfiram. The disparity may also reflect the predominantly nonmedical approach to treating alcohol dependence in Britain.

Synergistic toxicity of epigallocatechin-3-gallate and diethyldithiocarbamate, a lethal encounter involving redox-active copper

Dithiocarbamates (DTC) are widely used in agricultural, industrial and therapeutic domains. There are ample opportunities for human exposure to DTC. Green tea extracts, with epigallocatechin-3-gallate (EGCG) being the most abundant constituent, have been used as dietary supplements for body weight reduction. Our hypothesis is that DTC can act as a copper ionophore to increase hepatic levels of redox-active copper which promotes EGCG auto-oxidation to produce oxidative stress and toxicity. The results of the present study in a mouse model is consistent with this hypothesis, showing that co-administration of EGCG and diethyldithiocarbamate - a metabolite of disulfiram (a drug for alcohol aversion therapy), both at tolerable levels, caused lethality. The liver was the major organ site of toxicity. The co-administration drastically increased lipid peroxidation, DNA damage and cell apoptosis as well as caused deleterious transcriptional responses including basal and Nrf2 antioxidant systems in the liver. The results suggest that exposure to DTC reduces toxic threshold of dietary polyphenols from green tea and possibly other plants, and vice versa. This novel hypothesis is important to human health, and the dose-response relationship of this synergistic toxicity needs to be further characterized.

Alcohol addiction - the safety of available approved treatment options

INTRODUCTION

Alcohol Use Disorders (AUD) is a leading cause of mortality and morbidity worldwide. At present disulfiram, naltrexone and acamprosate are approved for the treatment of AUD in U.S. and Europe. Nalmefene is approved in Europe and sodium oxybate is approved in Italy and Austria only. Baclofen received a 'temporary recommendation for use' in France.

AREAS COVERED

The safety of the above mentioned medications on liver, digestive system, kidney function, nervous system, pregnancy and lactation and their possible side effects are described and discussed.

EXPERT OPINION

Mechanism of action and metabolism of these drugs as well as patients' clinical characteristics can affect the safety of treatment. All approved medications are valid tools for the treatment of AUD in patients without advanced liver disease. For some drugs, attention should be paid to patients with renal failure and medications may be used with caution, adjusting the dosage according to kidney function. In patients with AUD and advanced liver disease, at present only baclofen has been formally tested in randomized controlled trials showing its safety in this population.

Acute pneumonitis associated with nickel carbonyl exposure in the workplace

BACKGROUND

We describe the clinical course of one industrial technician occupationally exposed to nickel carbonyl (NiC).

CASE REPORT

A 50-year-old male industrial technician presented with complaints of nausea, myalgia, and cough to a local clinic after suspected occupational exposure to nickel carbonyl. He has no history of lung disease or smoking. His initial urine nickel concentration was 692 ug/L. He had infiltrates on the initial chest X-ray (CXR) and an oxygen saturation (O₂) of 97% on room air. The patient was started on disulfiram 1 g by mouth (PO), 500 mg six hours after the first dose, then 250 mg twice daily for five days with prednisone 60 mg by mouth for five days. He presented 48 hours later with worsening respiratory symptoms. His O₂ saturation decreased to 85% despite two days of oral steroids, and he was admitted to a hospital. He received prednisone 60 mg/day PO, 4 L nasal O₂, and disulfiram 500 mg twice daily. He was discharged on day 7 post-exposure with disulfiram and prednisone. Case discussions: NiC is a severe respiratory irritant. Disulfiram was used off-label and was based on an established company protocol.

CONCLUSIONS

Inhalation exposure to NiC resulted in a delayed respiratory dysfunction which responded to disulfiram treatment.

Alcoholic liver disease and hepatitis C virus infection

Alcohol consumption and hepatitis C virus (HCV) infection have a synergic hepatotoxic effect, and the coexistence of these factors increases the risk of advanced liver disease. The main mechanisms of this effect are increased viral replication and altered immune response, although genetic predisposition may also play an important role. Traditionally, HCV prevalence has been considered to be higher (up to 50%) in alcoholic patients than in the general population. However, the presence of advanced alcoholic liver disease (ALD) or intravenous drug use (IDU) may have confounded the results of previous studies, and the real prevalence of HCV infection in alcoholic patients without ALD or prior IDU has been shown to be lower. Due to the toxic combined effect of HCV and alcohol, patients with HCV infection should be screened for excessive ethanol intake. Patients starting treatment for HCV infection should be specifically advised to stop or reduce alcohol consumption because of its potential impact on treatment efficacy and adherence and may benefit from additional support during antiviral therapy. This recommendation might be extended to all currently recommended drugs for HCV treatment. Patients with alcohol dependence and HCV infection, can be treated with acamprosate, nalmefene, topiramate, and disulfiram, although baclofen is the only drug specifically tested for this purpose in patients with ALD and/or HCV infection.

Pharmacotherapy for alcohol addiction in a patient with alcoholic cirrhosis and massive upper gastrointestinal bleed: A case study

Alcohol use causes a substantial burden of morbidity and mortality worldwide. The pharmacologic treatment of alcohol dependence has been increasingly studied and proven to improve outcomes in individuals with alcohol use disorder. However, the treatment of alcohol use disorder is often challenging in the context of patients with hepatic impairment as many medications to treat alcohol use disorder are hepatically metabolised or may cause liver toxicity in some instances. We present a case history of an individual with significant medical complications from alcohol use disorder and explore the dilemma faced in prescribing pharmacologic treatment of alcohol use disorder in patients with significant liver dysfunction.

Alcoholic hepatitis: Prognosis and treatment

Alcoholic hepatitis (AH) is a type of acute-on-chronic liver failure and is the most severe form of alcoholic liver disease. AH occurs in patients with heavy alcohol abuse and underlying liver disease. In its severe form, AH carries a poor short-term prognosis. Although the existence of AH can be strongly suspected based on clinical and biochemical criteria, a definitive diagnosis requires a liver biopsy. There is a clear need to develop non-invasive markers for these patients. The prognosis of patients with AH can be established by different score systems (Maddrey's DF, ABIC, MELD and Glasgow). Recently, a histological scoring system able to estimate prognosis has been developed (Alcoholic Hepatitis Histological Score - AHHS). The management of patients with AH has changed little in the last few decades. In patients with severe form of AH, prednisolone and pentoxifylline are the first line therapy. Unfortunately, many patients do not respond and novel targeted therapies are urgently needed. Current research is aimed at identifying the main disease drivers and to develop animal models of true AH. For non-responders to medical therapy, the only curative option is to perform a salvage liver transplantation. This particular indication of liver transplantation is currently under debate and prospective studies should evaluate the specific patient evaluation and selection criteria.

Management of alcohol dependence in patients with liver disease

Alcohol dependence represents a chronic and relapsing disease affecting nearly 10 % of the general population both in the USA and in Europe, with a widespread burden of morbidity and mortality. Alcohol dependence represents the most common cause of liver damage in the Western world. Although alcoholic liver disease is associated primarily with heavy drinking, continued alcohol consumption, even in low doses after the onset of liver disease, increases the risk of severe consequences, including mortality. Consequently, the ideal treatment of patients affected by alcohol dependence and alcoholic liver disease should aim at achieving long-term total alcohol abstinence and preventing relapse. The aim of the present review is to provide an update on the management of alcohol dependence in patients with alcoholic liver disease. Increasing evidence suggests the usefulness of psychosocial interventions and medications combined in order to reduce alcohol intake, promote abstinence and prevent relapse in alcohol-dependent patients. Disulfiram, naltrexone and acamprosate have been approved for this indication; gamma-hydroxybutyric acid (GHB) is approved in Italy and Austria. However, these drugs have not been tested in patients with advanced liver disease. Amongst other emerging pharmacotherapies for alcoholism, topiramate, ondansetron, and baclofen seem the most promising ones. Both topiramate and ondansetron have a safe profile in alcoholic patients; however, none of them has been tested in alcoholic patients with advanced liver disease. To date, baclofen represents the only anti-craving medication formally tested in a randomized clinical trial in alcoholic patients affected by liver cirrhosis, although additional confirmatory studies are warranted.

Pre-clinical safety evaluation of pyrrolidine dithiocarbamate

Pyrrolidine dithiocarbamate (PDTC) was examined for its potential in the intranasal treatment of human rhinovirus infections. Prior to clinical testing, a comprehensive non-clinical programme was performed to evaluate the general toxicity of PDTC. The animal experiments included investigations in rodents with study durations ranging from single dose to repeated dosing over a period of 28 days. The routes of administration were intranasal, inhalative, oral and intravenous for single-dose toxicity and pharmacokinetic studies, and intranasal for repeated dose studies. Blood and tissue samples were obtained from PDTC-treated rats to analyse pharmacokinetics and tissue distribution. Accumulation of selected metals due to PDTC treatment was examined in liver, brain, nerves and fat tissues.

Management of alcoholic liver disease

Understanding alcohol addiction and abstinence is key to treating alcoholic liver disease, since abstinence leads to improvement in all forms of alcoholic liver damage. Although pharmacotherapy for alcoholism, using agents such as naltrexone, acamprosate, topiramate, and baclofen, is an exciting field, few studies have included patients with liver disease or cirrhosis. To treat alcoholic liver injury, corticosteroids have become the standard of care in patients with severe alcoholic hepatitis. In contrast, the role of pharmacotherapy to treat alcoholic fibrosis is unclear, with failure to observe a benefit in randomized, placebo-controlled clinical trials of colchicine, S-adenosylmethionine (SAMe), or phosphatidylcholine. Liver transplantation remains an option in selected patients with life-threatening alcoholic liver disease.

Protein S-glutathionylation and platelet anti-aggregating activity of disulfiram

Blood platelets are central to haemostasis, and reactions in platelets involving sulfhydryl groups play important roles in platelet function. Reduced glutathione (GSH) plays an important role in platelet aggregation and glutathione-depleting chemicals inhibit platelet aggregation. The lipophilic drug disulfiram, because of its affinity for sulfhydryl groups, is a highly thiol-reacting agent. As a consequence, GSH and sulfhydryl groups of protein cysteines in human platelets, in analogy to other components of human blood, are a potential target of disulfiram. In the present study, we have shown that exposure of human platelets to disulfiram causes the depletion of platelet GSH and augmentation of mixed disulfides between GSH and protein sulfhydryl groups to form protein-glutathione mixed disulfides (S-glutathionylated proteins). The depletion of platelet GSH and the increase in S-glutathionylated proteins occurred at concentrations of disulfiram that inhibited platelet aggregation, suggesting that protein S-glutathionylation is involved in the inhibition of platelet aggregation caused by disulfiram.

Clinical characteristics and prognostic markers in disulfiram-induced liver injury

BACKGROUND/AIMS

Limited systematic data exists on the incidence of drug-induced hepatotoxicity due to disulfiram and the most important prognostic markers. We aimed to determine the nature and frequency of suspected disulfiram hepatotoxicity in Sweden.

METHODS

All reports of suspected hepatic adverse drug reactions (ADR) associated with disulfiram received by the Swedish Adverse Drug Reactions Advisory Committee (SADRAC) 1966-2002 were reviewed. Causality assessment was based on the International Consensus Criteria.

RESULTS

A total of 82 reports of disulfiram suspected ADRs had at least a possible causal relationship. Eight patients died or underwent liver transplantation (Tx). Mortality or Tx was 16% in patients with jaundice. The median age of the patients (65% males) was 45 years with a median duration of treatment of 42 days. Bilirubin was higher (P<0.0001) in the deceased/transplanted patients compared to surviving patients. No difference was observed in age or duration of therapy between deceased and transplanted and those who recovered. Eosinophilic infiltration in liver biopsies was associated with a favourable outcome, hepatocyte drop-out with a poor outcome.

CONCLUSIONS

Disulfiram associated hepatitis has a considerable mortality risk. Histological signs of immunoallergy seem to be common. Bilirubin and hepatocyte drop-out were the only predictors for death or transplantation.

Dietary Copper Enhances the Peripheral Myelinopathy Produced by Oral Pyrrolidine Dithiocarbamate

The neurotoxic hazard of a dithiocarbamate is influenced by route of exposure and acid stability of the dithiocarbamate. As an example, oral administration of the acid labile dithiocarbamate N,N-diethyldithiocarbamate (DEDC) causes a central-peripheral axonopathy thought to result from acid-promoted decomposition to CS2 in the stomach. In contrast, parenteral administration of DEDC, which bypasses the acidic environment of the stomach, causes a primary demyelination that is thought to be mediated through the intact parent dithiocarbamate. The relative acid stability of pyrrolidine dithiocarbamate (PDTC) suggests that a significant portion of a dose can be absorbed intact following oral exposure with the potential to produce a primary myelin injury. The present study was performed to characterize the neurotoxicity of PDTC and evaluate the possible role of copper in dithiocarbamate-mediated demyelination. Male Sprague Dawley rats were administered PDTC in drinking water and given either a normal- or high-copper diet for 18, 47, or 58 weeks. Examination of peripheral nerve by light microscopy and electron microscopy at the end of exposures revealed primary myelin lesions and axonal degeneration in the PDTC groups, with a significant increase in the severity of several lesions observed for the PDTC, high-copper group relative to the PDTC normal-copper diet. ICP-AES metal analysis determined that the PDTC groups had significantly increased brain copper, and at 58 weeks a significant increase in copper was seen in the sciatic nerve of PDTC high-copper animals relative to PDTC normal-copper diet animals. Although RP-HPLC analysis could not detect globin alkylaminocarbonyl cysteine modifications analogous to those seen with parenteral DEDC, LC/MS/MS identified (pyrrolidin-1-yl carbonyl)cysteine adducts on PDTC-exposed rat globin. These findings are consistent with previous studies supporting the ability of acid-stable dithiocarbamates to mediate myelin injury following oral exposure. The greater severity of lesions associated with dietary copper supplementation and elevated copper levels in nerve also suggests that perturbation of copper homeostasis may contribute to the development of myelin lesions.

Liver transplantation for disulfiram-induced fulminant hepatic failure

Disulfiram has been used as a popular adjunct in programs for alcohol rehabilitation. However, in rare cases, disulfiram has been reported to cause fulminant hepatitis. Disulfiram use and its associated complications in adolescents have received minimal attention in the literature. We report the first pediatric case of successful orthotopic liver transplantation for disulfiram-induced fulminant hepatic failure in a 16-year-old girl, who developed an idiosyncratic reaction associated with short-term, low-dose disulfiram use, as evidenced by her liver biopsy and explanted liver. This case report indicates that a high index of suspicion, and aggressive therapeutic interventions are necessary to recognize and manage disulfiram-induced fulminant hepatic failure in adolescents. Success of this case suggests that transplant centers should consider liver transplantation of an adolescent alcoholic patient with fulminant hepatic failure due to non-alcohol-related causes such as disulfiram. Orthotopic liver transplantation should be considered early in the management of disulfiram-induced fulminant hepatic failure.

Fulminant liver failure associated with clarithromycin

OBJECTIVE

To report a patient developing fulminant liver failure while being treated with clarithromycin for pneumonia.

CASE SUMMARY

A 58-year-old white woman developed fulminant liver failure while being treated with the macrolide antibiotic clarithromycin for pneumonia. Comedication included N-acetylcysteine, atenolol, and isradipine. Other causes of liver failure, such as viral hepatitis, autoimmune hepatitis, toxins, and heart failure, were excluded by appropriate diagnostic means. All drugs were stopped, and the patient was transferred to another hospital for liver transplantation. She recovered spontaneously within several days, making transplantation unnecessary. A liver biopsy obtained 10 days after the initial presentation revealed centroacinar necrosis and beginning fibrous reorganization, compatible with recent centroacinar damage.

DISCUSSION

Since no other cause could be identified, liver injury was considered to be drug related. Fulminant liver failure has not previously been described with concomitant use of atenolol and N-acetylcysteine. Although isradipine has been associated with hepatocellular injury, there are no reports of fulminant liver failure with this agent, and our patient had been treated for >2 years without signs of toxicity. The most likely cause of liver failure in this patient was, therefore, clarithromycin, which undergoes hepatic metabolism and has been reported to cause fulminant hepatic failure. A second possibility is an interaction between clarithromycin and isradipine, potentially increasing the hepatic toxicity of isradipine.

CONCLUSIONS

Clarithromycin may be a cause of fulminant liver failure either alone or by inhibiting the metabolism of other drugs.

Preventing disulfiram hepatitis in alcohol abusers: inappropriate guidelines and the significance of nickel allergy

Disulfiram hepatitis, although sometimes fatal, is a very rare complication of alcoholism treatment. A disproportionate number of cases are associated with disulfiram treatment for nickel allergy and unrecognized nickel sensitivity may partly explain the surprisingly high proportion of female victims- about 60%. US guidelines formulated in 1988 suggest that alcoholic patients should not be started on disulfiram unless liver toxicity tests have been done and, if elevated, returned to normal. This advice is unsound and contrasts with medical attitudes to the prevention of other rare side effects. It has led to significant delays in starting treatment which are probably much more hazardous than the very slight risks of hepatotoxicity. We recommend that the guidelines be modified in favour of an approach which emphasizes the education of patients and their carers and clinical rather than laboratory monitoring.

Safety issues concerning the use of disulfiram in treating alcohol dependence

Disulfiram is known to cause hepatitis, which is sometimes fatal. The best estimate of the frequency of disulfiram-induced fatal hepatitis is 1 case in 30,000 patients treated/year. Its appears to be more common in patients given disulfiram for the treatment of nickel sensitivity. Frequent blood testing for liver function is probably not necessary, but patients taking disulfiram should be in regular contact with a physician. There are rare reports of psychosis and confusional states in conjunction with disulfiram treatment and peripheral neuropathy and optic neuritis have been reported; these effects are dose-related. Psychiatric complications appear to be more common with the use of disulfiram in India than in Western countries. Of the less serious adverse effects, tiredness, headache and sleepiness are the most common. Deaths from the disulfiram-alcohol (ethanol) interaction have not been reported in recent years, possibly because the dosages used are lower than those used 40 years ago, and patients with cardiac disease are now excluded from treatment. There is no evidence to suggest that disulfiram causes cancer. Of note, there are drug interactions with compounds that utilise the cytochrome P450 enzyme system. Disulfiram can be viewed as a drug with a moderate record of adverse effects. Alcohol dependence, for which it can be a helpful treatment, is associated with a high morbidity and mortality.

Expression of autoantibodies to specific cytochromes P450 in a case of disulfiram hepatitis

BACKGROUND/AIMS

Immunological mechanisms are involved in many adverse drug reactions. In certain forms of drug-induced hepatitis, patients have been reported to express specific autoantibodies to hepatic drug-metabolising enzymes. The alcohol deterrent disulfiram is associated with a low frequency of severe liver toxicity, including hepatitis, but the mechanism of the toxicity is unknown. We investigated whether autoantibodies to cytochrome P450 enzymes were expressed in the serum of a 28-year-old male patient, who developed hepatitis after 7 weeks of disulfiram treatment and in whom possible causes of hepatitis other than disulfiram had been ruled out.

METHODS

Patient serum IgG reactivity was analysed by immunoblotting or ELISA against test antigens consisting of recombinant/purified human or rat liver P450 enzymes, or isolated rat liver microsomes.

RESULTS

A significant serum reactivity was found in immunoblotting against human cytochromes P450 1A2 and rat P450 3A1, using serum dilutions of up to 1:900 and 1:2400, respectively. In contrast, the reactivity against cytochromes P450 2E1, 2C9, 2D6, 3A4, and rat liver P450 reductase was either very low or undetectable. ELISA reactivity was low in general, indicating that the P450 epitopes were not surface exposed. Immunoblotting of rat liver microsomes revealed that autoantibodies recognised one major polypeptide corresponding to P450 3A. Autoantibody titres remained stable for at least 6 months after acute hepatitis. A similar reactivity was not found in any of ten control sera.

CONCLUSIONS

The expression of autoantibodies directed against specific cytochromes P450 in a case of disulfiram hepatitis suggests that immunological mechanisms are involved in this adverse drug reaction, and that these P450 proteins should be evaluated as possible diagnostic test antigens in disulfiram hepatotoxicity.

Pharmacological treatment of alcoholism

1. Pharmacological treatments are effective as part of a treatment plan that includes substantial education, psychological therapy and social support. This paper reviews recent literature on animal models of and treatment for alcohol abuse under seven categories: agents to block craving or reduce alcohol intake, agents to induce aversion to alcohol, agents to treat acute alcohol withdrawal, agents to treat protracted alcohol withdrawal, agents to diminish drinking by treating associated psychiatric pathology, agents to decrease drinking by treating associated drug abuse, and agents to induce sobriety in intoxicated individuals. 2. The benzodiazepines provide safe and effective treatment for detoxification, although current research focuses on finding drugs with a smaller likelihood of dependence. As yet, there are no drugs that effectively reverse the intoxicating effects of alcohol. 3. Currently, only two major groups of drugs that are relatively safe have shown any effect at reducing alcohol consumption: aversives such as disulfiram, and opioid antagonists such as naltrexone. 4. Finally, it is important to customize therapy for each patient rather than putting everyone through a standard treatment plan, especially in regards to the use of antidepressant or antipsychotic medications. Tailoring the program to the patient's needs dramatically improves the outcome of therapy and reduces the risk of adverse effects.