The study aims (i) to identify which substances leading to hospitalizations at Mayotte are also called "chimique" and (ii) to correlate these substances with clinical pictures in order to favor a better approach of the treatments.

The CEIP-A of Bordeaux (in charge of French overseas departments) has been commissioned by the MILD&CA in 2015 to reinforce the links between local caregivers and the addictoviligance's inquieries. In particular, the CEIP-A has been alerted about a drug called " chimique " in Mayotte, leading to many hospitalizations. Most of the patients are less than 18 year old or are young adulthoods. For all patients who have agreed to participate in this study, the remainder of the blood sample will be reused for a drop of blood on blotting paper; the remainder of the remainder will be stored in the heparinized tube. Medical data collected in the emergency department will also be collected. All the data will be analyzed by the pharmacology and toxicology laboratory of the Bordeaux University Hospital

Inclusion Criteria:

• Patients hospitalized in the Emergency Department of the Mayotte Hospital Center after taking a chemical or other psychoactive substance and for whom a blood test is required;
• Age ≥ 14 years.

Exclusion Criteria:

• Patient without parental authority for minor patients aged 14yrs; Patient not included in the exception article 59 of the law of January 6th, 1978 modified for patient aged 15yrs and older

Patients hospitalized in the Emergency Department of the Mayotte Hospital Center after taking a chemical or other psychoactive substance