A method for the immediate detection of an active principle which modifies the state of consciousness of a victim illicitly introduced into a drink, said method comprising: * dissolution in a drink of a pharmaceutical form consisting of: - an active principle which modifies the state of consciousness of a victim, - at least 0.05 mg, preferably from 0.2 to 5 mg, still more preferably from 0.3 to 2 mg of a watersoluble coloring agent selected from indigocarmine, erythrosine, brilliant blue FCF, alphazurine FG, fast green FCF, quinzarin green SS, orange II, tartrazine and sunset yellow FCF, - particles perceptible in the mouth and floating having a density less than one and a diameter greater than 500 μm, said particles being microgranules comprising a blank support which is insoluble or rendered insoluble in water or in an alcoholic solution by coating with a lipid material or by coating with an insoluble polymer, - at least one pharmaceutically acceptable excipient, said pharmaceutical form being a solid non-film-coated pharmaceutical form being presented in the form of chewable tablet or orodispersible tablet; * detection of the pharmaceutical form in said drink through the immediate modification of the organoleptic properties of the drink, the modification of the organoleptic properties taking place in less than one minute, preferably in less than 30 seconds, still more preferably in less than 15 seconds from the introduction of the pharmaceutical form in the drink. * dissolution in a drink of a pharmaceutical form consisting of: - an active principle which modifies the state of consciousness of a victim, - at least 0.05 mg, preferably from 0.2 to 5 mg, still more preferably from 0.3 to 2 mg of a watersoluble coloring agent selected from indigocarmine, erythrosine, brilliant blue FCF, alphazurine FG, fast green FCF, quinzarin green SS, orange II, tartrazine and sunset yellow FCF, - particles perceptible in the mouth and floating having a density less than one and a diameter greater than 500 μm, said particles being microgranules comprising a blank support which is insoluble or rendered insoluble in water or in an alcoholic solution by coating with a lipid material or by coating with an insoluble polymer, - at least one pharmaceutically acceptable excipient, said pharmaceutical form being a solid non-film-coated pharmaceutical form being presented in the form of chewable tablet or orodispersible tablet; - an active principle which modifies the state of consciousness of a victim, - at least 0.05 mg, preferably from 0.2 to 5 mg, still more preferably from 0.3 to 2 mg of a watersoluble coloring agent selected from indigocarmine, erythrosine, brilliant blue FCF, alphazurine FG, fast green FCF, quinzarin green SS, orange II, tartrazine and sunset yellow FCF, - particles perceptible in the mouth and floating having a density less than one and a diameter greater than 500 μm, said particles being microgranules comprising a blank support which is insoluble or rendered insoluble in water or in an alcoholic solution by coating with a lipid material or by coating with an insoluble polymer, - at least one pharmaceutically acceptable excipient, said pharmaceutical form being a solid non-film-coated pharmaceutical form being presented in the form of chewable tablet or orodispersible tablet; * detection of the pharmaceutical form in said drink through the immediate modification of the organoleptic properties of the drink, the modification of the organoleptic properties taking place in less than one minute, preferably in less than 30 seconds, still more preferably in less than 15 seconds from the introduction of the pharmaceutical form in the drink.