Weight loss at a cost: A case of sibutramine-induced psychotic disorder

Abstract

Background

Sibutramine was once a commonly prescribed medication for weight management. However, it was ultimately removed from the market due to its link to serious cardiovascular risks such as stroke and myocardial infarction. While its primary function is to suppress appetite, sibutramine has also been known to trigger a range of psychiatric symptoms, including anxiety, depression, and psychosis.

Objective

To present a case highlighting the potential mental health implications associated with the use of sibutramine.

Methods

This article presents a case report; clinical details were documented by the psychiatrist in charge and reviewed by the team. The Naranjo adverse drug reaction Probability Scale was used in this case to evaluate whether the psychotic events were associated with sibutramine use.

Results

a young female developed severe psychiatric symptoms requiring hospitalization after using sibutramine for weight loss. Treatment included suspending sibutramine and administering Aripiprazole 15 mg.

Conclusion

This case serves as a poignant reminder of the potential dangers associated with using unregulated medications for weight loss purposes and underscores the importance of seeking professional medical guidance when embarking on any kind of treatment regimen.

Introduction

Sibutramine, a serotonin-norepinephrine reuptake inhibitor (SNRI), was widely prescribed for weight management previously (Ullah and Tamanna, 2025). It was withdrawn from the market due to its association with cardiovascular risks (Carles et al., 2025). A recent clinical trial has demonstrated weight-losing effect of sibutramine and topiramate (Cercato et al., 2025). Although its primary action is to reduce appetite, sibutramine has been documented to induce various psychiatric symptoms, including memory impairment, anxiety, depression, and psychosis (Cercato et al., 2025; Johansson et al., 2010). The underlying mechanism for this occurrence remains unclear. There is no established treatment guideline specifically for sibutramine-associated psychosis; management typically involves standard antipsychotic therapy, such as Aripiprazole ‒ as used in our case ‒ and, importantly, discontinuing sibutramine (Câmara Pestana et al., 2022; Ferreira et al., 2018; Waszkiewicz et al., 2012). A similar therapeutic approach has been discussed in previous literature and has demonstrated effectiveness in multiple case studies. Development of suicidal ideation was reported in one of the case studies (Câmara Pestana et al., 2022). Studies about the quality of over-the-counter medications reported that sibutramine was the most common adulterant with psychosis being one of the most frequently encountered adverse effects; although there are indications of a potential association between sibutramine use and psychosis, definitive evidence is yet to be established (Chen et al., 2010; Ching et al., 2018).

This article presents a case study of psychotic symptoms related to sibutramine use and explores the implications for diagnosis and treatment. The exact dose of sibutramine taken by the patient is undetermined, and the potential adulteration of these over-the-counter medications further complicates the case (Chen et al., 2010; Ching et al., 2018). This case is contextualised with a review of the current literature on sibutramine-induced psychiatric disorders. This study highlights the significance of avoiding unregulated medication for supplement or cosmetic use, and describes the approach used to treat sibutramine-associated psychosis, given its uncommon occurrence. This also underscores the need for thorough history taking in clinical practice, as supplements or cosmetic medications are often overlooked; a complete history can help identify potential causes of disease.

The Naranjo adverse drug reaction Probability Scale was used in this case to evaluate whether the psychotic events were associated with sibutramine use. This scale is originally designed to standardise causality assessment for adverse drug reactions (LiverTox: Clinical and Research Information on Drug-Induced Liver Injury, 2012). Although the scale was primarily developed for use in controlled trials and registration studies rather than routine clinical practice, it has been applied here to assist in evaluating the potential link between sibutramine and the observed psychosis, due to reports of relatively novel adverse effects.

Case presentation

A female patient in her mid-20s presented to mental health services with acute psychotic symptoms lasting for 3 weeks. She experienced persecutory delusions as she believed that her flatmates were conspiring with the government to murder her and that the hospital staff were poisoning her food. She heard second-person auditory hallucinations which were derogatory towards herself and her family. This marked her third episode of psychosis within a year, all occurring after self-administering sibutramine, a weight-loss medication she had used intermittently due to long-standing weight concerns since her early teens. During her adolescence, she discontinued sibutramine use as it caused her anxiety, depression, and insomnia, but resumed it after migrating to the UK for her studies, leading to recurrent psychotic episodes. On presentation, she was agitated, dishevelled, actively hallucinating, lacked insight, and was assessed as having impaired capacity. She was initially prescribed Aripiprazole 15 mg, which had previously managed her symptoms, but further assessment suggested a possibility of sibutramine-induced psychotic disorder. She was agreed to have a medication-free period and remained well without the need for any psychotropics during those days even though her preoccupation with weight loss persisted, indicating a possible underlying eating disorder. Despite psychoeducation, she expressed a desire to continue using sibutramine, resulting in a relapse of her psychotic symptoms associated with increased pulse rate, blood pressure and symptoms suggestive of panic attacks following its use. These resolved again after discontinuing sibutramine. Considering the possibility of quick relapse with the sibutramine use in future, reinitiating Aripiprazole at 10 mg/day was planned. She was subsequently referred to an eating disorder team to address her preoccupations with weight loss despite her having no other typical signs and symptoms that would suggest a formal diagnosis of any type of eating disorder.

Discussion

Sibutramine has been associated with psychiatric disturbances, including psychosis. It continues to pose risks even after its market withdrawal via illicit or online purchase as seen in this case. Diagnosing substance-induced psychosis requires careful evaluation of the temporal relationship between substance use and symptom onset. Recurring psychotic symptoms following sibutramine use support the diagnosis. Naranjo criteria were used to support this clinical observation (Doherty, 2009). The total score obtained was 6. The score denoted that this reaction to sibutramine could be considered probable.

Literature on sibutramine-induced psychosis, though rare, documents cases often in individuals with pre-existing psychiatric vulnerabilities (Gazdag and Szabó, 2008). In this case, patient reported financial crisis and insecurities owing to her academic stress, migration and political situation in her home country. Management of her symptoms involved discontinuing the substance, administering antipsychotic treatment, and addressing underlying conditions like eating disorders. Aripiprazole, an atypical antipsychotic effective in managing our patient's symptoms, presented challenges due to its potential for weight gain.

This necessitated consideration of adjunctive treatments to ensure adherence and highlighted the need for a multidisciplinary approach. The integration of psychiatry, psychology, and dietetics, to address both psychotic symptoms and underlying weight preoccupations was crucial for preventing relapses and achieving long-term recovery. Other factors may also explain her psychotic symptoms, such as relocating to a new country, being away from family, and studying a high-stress subject at university; these stressors could also contribute to her condition. Given that she previously experienced adverse reactions to the medication and her symptoms improved after discontinuing the substance, sibutramine misuse is likely responsible in this situation.

Sibutramine, like many other serotonin–norepinephrine–dopamine reuptake inhibitors, might provoke psychotic symptoms ‒ such as delusions and hallucinations ‒ through elevated dopaminergic activity in mesolimbic pathways, particularly in vulnerable individuals (An et al., 2013). This effect is often reversible upon discontinuation of the drug. There is little evidence for the mechanism behind sibutramine-induced psychosis.

Conclusion

Sibutramine-induced psychotic disorder highlights the critical need for awareness of the psychiatric side effects of weight loss medications. Effective management requires a comprehensive approach that addresses both the psychiatric symptoms and the underlying issues driving substance use. With the rise of online pharmacies, healthcare providers must remain vigilant in assessing the potential for substance-induced disorders in patients presenting with new-onset psychosis.