Objective: This case report highlights the risk of Torsade de Pointes (TdP), a life threatening cardiac arrhythmia in a heroin dependent patient receiving methadone substitution therapy who was prescribed erythromycin for upper respiratory tract infection. Method: We report a case of a 35-year-old Malay man on methadone maintenance treatment who developed TdP possibly due to drug interaction between methadone and erythromycin. Results: The
patient reported feeling unwell, chest pain and feeling dizzy after consuming 2 doses of erythromycin. ECG monitoring showed prolonged rate-corrected QT interval leading to TdP. The patient was admitted to the ward where the cardiac arrhythmia ceased following methadone discontinuation. This cardiac arrhythmia was most likely due to drug interaction between methadone and erythromycin (an enzyme inhibitor) which led to an increase in methadone concentration and potentiated the adverse effects. Conclusion: As methadone is a beneficial treatment for heroin dependent patients, the risk of cardiac arrhythmia is of great concern. To avoid complications of drug interaction, patients on methadone therapy should be advised to seek medical assessment before taking other drugs. As TdP is life threatening, it is thus important that physicians and psychiatrists involved in the treatment of
heroin dependent patients on methadone substitution therapy be made aware of this risk.
Objective: This case report highlights the abuse and dependence potential of Zolpidem and the risk of life-threatening withdrawal symptoms upon abrupt discontinuation. Method: We report a case of Zolpidem dependence which presented with withdrawal symptoms upon abrupt discontinuation. Results: A 32 year old male, who had abused non-benzodiazepine Zolpidem for 6 years presented to the accident and emergency unit with generalized seizures upon stopping Zolpidem ‘cold turkey’. He required admission to the neurology high dependency unit for stabilization of the seizures and was later managed by the addiction team where a tapering dose of benzodiazepine was prescribed. Conclusion: This case demonstrates that non-benzodiazepine agents can cause tolerance and dependence, and thus produce withdrawal symptoms upon discontinuation.
Objective: The smoking rate among patients with mental health problem is higher than in the general population. Effective pharmacotherapy to treat nicotine addiction is thus needed to reduce the morbidity and mortality associated with cigarette smoking among these patients. This article reviews the literature on the suitability of varenicline for smokers with mental health problems.
Methods: A search of the literature was conducted using PubMed from year 2001 to July 2009 using key words varenicline alone and varenicline and mental health. Articles chosen were narrowed to those published in English. The type of articles chosen included clinical trials, metaanalyses, case reports, and review articles.
Results: The search produced a total of 322 articles on varenicline and 14 articles on varenicline and mental health. Varenicline, a new drug for smoking cessation is an α4β2 partial agonist and partial antagonist at nicotinic acetylcholine receptor. As a partial agonist, varenicline relieves craving and withdrawal symptoms that occur during smoking abstinence and also reduce the rewarding effects of smoking in patients who relapse. However, at present, there is concern regarding the neuropsychiatric side effects such as aggressive behaviour, suicidal ideation, mania and depression associated with varenicline use in patients with mental health problems, but these reports did not show a causal-link or lack of link between these symptoms and varenicline.
Conclusion: Current available data support the effectiveness of varenicline to treat nicotine dependence. However its safety among smokers with mental health problems remains to be elucidated. At present, further safety assessment is needed in this patient population. Until new data is available regarding the safety of varenicline in these populations, psychiatrists and physicians prescribing this medication should be extra cautious and monitor for possible psychiatric side effects when prescribing this medication to patients with pre-existing psychiatric disorders or have vulnerability to psychoses.