Metformin abuse: A novel and dangerous purging behavior in anorexia nervosa

Iatrogenic triggers for anorexia nervosa and bulimia nervosa: A WHO safety database disproportionality analysis

Eating disorders, characterized by abnormal eating, weight control behaviors or both include anorexia nervosa (AN) and bulimia nervosa (BN). We investigated their potential iatrogenic triggers, using real-world data from the WHO safety database (VigiBase®). VigiBase® was queried for all AN and BN reports. The reports were classified as `pediatric' or `adult' according to age. Disproportionality analyses relied on the Information Component (IC), in which a 95% confidence interval lower-end positivity was required to suspect a signal. Our queries yielded 309 AN and 499 BN reports. Isotretinoin was disproportionately reported in pediatric AN (IC 3.6; [2.6-4.3]), adult AN (IC 3.1; [1.7-4.0]), and pediatric BN (IC 3.9; [3.0-4.7]). Lamivudine (IC 4.2; [3.2-4.9]), nevirapine (IC 3.7; [2.6-4.6]), and zidovudine (IC 3.4; [2.0-4.3]) had the highest ICs in adult AN. AN was associated with isotretinoin, anticonvulsants in minors, and antiretroviral drugs in adults. In adults, BN was related to psychotropic and hormonally active drugs. Before treatment initiation, an anamnesis should seek out mental health conditions, allowing the identification of patients at risk of developing or relapsing into AN or BN. In addition to misuse, the hypothesis of iatrogenic triggers for AN and BN should also be considered.

Is There a Risk for Semaglutide Misuse? Focus on the Food and Drug Administration's FDA Adverse Events Reporting System (FAERS) Pharmacovigilance Dataset

Recent media reports commented about a possible issue of the misuse of antidiabetics related to molecules promoted as a weight-loss treatment in non-obese people. We evaluated here available pharmacovigilance misuse/abuse signals related to semaglutide, a glucagon-like peptide-1 (GLP-1) analogue, in comparison to other GLP-1 receptor agonists (albiglutide, dulaglutide, exenatide, liraglutide, lixisenatide, and tirzepatide) and the phentermine-topiramate combination. To acheieve that aim, we analyzed the Food and Drug Administration's FDA Adverse Events Reporting System (FAERS) dataset, performing a descriptive analysis of adverse event reports (AERs) and calculating related pharmacovigilance measures, including the reporting odds ratio (ROR) and the proportional reporting ratio (PRR). During January 2018-December 2022, a total of 31,542 AERs involving the selected molecules were submitted to FAERS; most involved dulaglutide (n = 11,858; 37.6%) and semaglutide (n = 8249; 26.1%). In comparing semaglutide vs. the remaining molecules, the respective PRR values of the AERs 'drug abuse', 'drug withdrawal syndrome', 'prescription drug used without a prescription', and 'intentional product use issue' were 4.05, 4.05, 3.60, and 1.80 (all < 0.01). The same comparisons of semaglutide vs. the phentermine-topiramate combination were not associated with any significant differences. To the best of our knowledge, this is the first study documenting the misuse/abuse potential of semaglutide in comparison with other GLP1 analogues and the phentermine-topiramate combination. The current findings will need to be confirmed by further empirical investigations to fully understand the safety profile of those molecules.

A concealed history behind the disaster: Extremely rare presentations of metformin toxicity in a patient with body dysmorphic disorder

Metformin is a widely used anti-hyperglycemic agent with weight loss effect properties but besides its various utilities, despite being very rare, it has its characteristic toxicity and adverse effects when used in large doses and for the long-term or in patients with renal impairment. We presented here a case of a 36-year-old woman who developed several presentations with diverse features during three years comprising neuropathic symptoms, severe lactic acidosis, three episodes of cardiogenic shock, acute kidney injury, megaloblastic anemia, pancytopenia, and hyponatremia and did not receive a definite diagnosis after each presentation until when she inadvertently disclosed her abuse of extremely unusual doses of metformin during these three years with aim of weight reduction obsessively without knowing that her symptoms could pertain to metformin overdose. She was eventually diagnosed with a body dysmorphic disorder which led to unreasonable abuse of metformin pills that consequently caused its toxicity. Thereafter, with cease of metformin use and psychiatric treatment, her symptoms did not recur and she was doing well after one year of her last admission. Based on the review of the literature, this is the first case of metformin toxicity in a patient with body dysmorphic disorder who was affected with extremely rare features of this intoxication, nevertheless, every manifestation of the patient was discussed exhaustively according to the current and available medical literature.

Converging vulnerability factors for compulsive food and drug use

Highly palatable foods and substance of abuse have intersecting neurobiological, metabolic and behavioral effects relevant for understanding vulnerability to conditions related to food (e.g., obesity, binge eating disorder) and drug (e.g., substance use disorder) misuse. Here, we review data from animal models, clinical populations and epidemiological evidence in behavioral, genetic, pathophysiologic and therapeutic domains. Results suggest that consumption of highly palatable food and drugs of abuse both impact and conversely are regulated by metabolic hormones and metabolic status. Palatable foods high in fat and/or sugar can elicit adaptation in brain reward and withdrawal circuitry akin to substances of abuse. Intake of or withdrawal from palatable food can impact behavioral sensitivity to drugs of abuse and vice versa. A robust literature suggests common substrates and roles for negative reinforcement, negative affect, negative urgency, and impulse control deficits, with both highly palatable foods and substances of abuse. Candidate genetic risk loci shared by obesity and alcohol use disorders have been identified in molecules classically associated with both metabolic and motivational functions. Finally, certain drugs may have overlapping therapeutic potential to treat obesity, diabetes, binge-related eating disorders and substance use disorders. Taken together, data are consistent with the hypotheses that compulsive food and substance use share overlapping, interacting substrates at neurobiological and metabolic levels and that motivated behavior associated with feeding or substance use might constitute vulnerability factors for one another. This article is part of the special issue on 'Vulnerabilities to Substance Abuse'.

Specific interpretation of hair concentrations in 2 fatal metformin intoxication cases

Hair analysis is very useful for toxicological investigations since, by providing a wider detection window, it gives the possibility to perform a retrospective study on the historical consumption of a substance. Unfortunately, there are no data available for hair concentrations in metformin-related deaths. In this study, the authors present 2 cases of fatal metformin intoxication in which, for the first time, hair analysis was performed using a specific GC-MS/MS method. Metformin was tested positive in femoral blood (112.3 mg/L and 64.7 mg/L respectively) and cardiac blood (226.9 and 203.2 mg/L) of the two subjects. For case 1, other samples were also tested positive, including vitreous humor (31.1 mg/L) and gastric contents (773.5 mg/L). In case 2, metformin was measured at 844.9 mg/L in urine. Metformin hair concentrations were 28.3-44.8 and 22.5 ng/mg for both cases, respectively. The concentrations found in the 2 fatal cases are clearly higher than those obtained in a previous study with subjects under treatment (0.3-3.8 ng/mg) or those found in 3 post-mortem cases where metformin death was excluded (0.6-1.4 ng/mg). Excessive sweating during the agonal phase due to fatal hypoglycemia could explain these elevated concentrations as sweat can have contaminated the hair.