[Resistance to vitamin K antagonist revealing interaction with soy lecithin]. / Résistance aux antivitamines K révélant une interaction avec la lécithine de soja.

Vitamin K antagonists (VKA) are difficult to use because of a narrow therapeutic index and of a marked inter- and intra-individual variability among patients in the required dosage. This drug may interact with many other drugs and same with certain food compounds. We report the case of potential interaction between soy lecithin and Vitamin K antagonists in a 46 years-old woman. Subtherapeutic INR values were detected despite the increase gradually in dose and replacing acenocoumarol by fluindione. An enquiry of pharmacovigilance was conducted found the consumption of soy lecithin capsules. Fifteen days after its stopping, the INR values have really increased. Clinicians should think to the possibility of interaction between oral anticoagulants and food supplement that is increasingly used.

Gender-specific study of recurrent suicide attempts in outpatients with multiple substance use disorders.

BACKGROUND: people suffering from substance use disorders (SUD) often die by suicide, so that the prevention of suicide attempts (SA) remains a top priority in this population. SA recurrence is common and is associated with suicide death, but this phenotype has been overlooked in SUD populations. Thus, we aimed at identifying the risk factors of SA recurrence in SUD, controlling for both gender and levels of exposure to addictive substances, including tobacco. METHODS: we consecutively recruited 433 treatment-seeking outpatients with either opiate or cocaine use disorder and assessed their lifetime history of addictive and suicidal symptoms by standardized questionnaires. They were reliably classified as never, single or recurrent (≥ 2) suicide attempters, whose characteristics were identified by multinomial regression, stratified by gender; and compared to our previous work on serious SA in order to identify common or different risk profiles. RESULTS: 86/140 (61%) suicide attempters reported recurrence. The mean number of SA was 3.1. Recurrence was independently associated with psychiatric hospitalization in both genders, with nicotine dependence in men and with sedative use disorders in women. LIMITATIONS: psychiatric diagnoses were derived from the current medication regimen. CONCLUSION: specific and possibly avoidable/treatable risk factors for the recurrence of SA in SUD have been identified for the first time, opening new avenues for research and prevention in this high-risk population. Apart from nicotine dependence, these risk factors were very similar to those of serious SA. Although this comparison is indirect for now, it suggests a common liability towards suicidal behavior.

Mucosal lichenoid drug reaction associated with glimepiride: a case report.

We report the case of a 52-year-old man with type 2 diabetes, who developed severe mucosal erosions of the tongue, glans penis and perianal area, induced by glimepiride. A tissue biopsy was performed and revealed the characteristics of lichen planus (LP). The improvement of the patient's condition after withdrawal of glimepiride added to recurrence of the lesions when medication was reintroduced confirmed that the second generation anti-diabetic was the causative agent. To the best of our knowledge, this has not been reported previously.

Could the inter-individual variability in cocaine-induced psychotic effects influence the development of cocaine addiction? Towards a new pharmacogenetic approach to addictions.

Cocaine addiction is a chronic disease marked by relapses, co-morbidities and the importance of psychosocial consequences. The etiology of cocaine addiction is complex and involves three types of factors: environmental factors, factors linked to the specific effects of cocaine and genetic factors. The latter could explain 40-60% of the risk for developing an addiction. Several studies have looked for a link between cocaine addiction and the genes of the dopaminergic system: the genes DRD2, COMT, SLC6A3 (coding for the dopamine transporter DAT) and DBH (coding for the dopamine beta hydroxylase) but unfortunately very few well established results. Pharmacogenetic approach could be an interesting opportunity for the future. The gene DBH has particularly been linked with the psychotic effects caused by cocaine. This so-called cocaine-induced psychosis (CIP) or cocaine-induced paranoia may influence the development of cocaine addiction. Indeed, these psychotic symptoms during cocaine exposure could cause an aversive effect limiting the development of an addiction. Several functional alterations caused by different mutations of the genes involved in dopaminergic transmission (principally-1021C>T of the gene DBH, but also Val158Met of the gene COMT, TaqI A of the gene DRD2 and VNTR 9 repeat of the DAT) could result in a cocaine-induced psychosis prone phenotype. We are hypothesising that the appearance of CIP during the first contact with cocaine is associated with a lower risk of developing cocaine addiction. This protective effect could be associated with the presence of one or more polymorphisms associated with CIP. A pharmacogenetic approach studying combination of polymorphism could isolate a sub-group of patients at risk for CIPs but more favorably protected from developing an addiction. This theory could enable a better understanding of the protective factors against cocaine addiction and offer new therapeutic or preventive targets in vulnerable sub-groups exposed to cocaine.