The present invention relates to a drug for human use, having contraceptive and menstrual cycle controlling properties, characterized in that the said drug comprises N-acetyl-5-methoxytryptamine or melatonin, in a dose of 100-200 mg pro die, N-acetyl-2-bromo-5-methoxytryptamine or 2-bromomelatonin in a dose of 25-50 mg pro die N-acetyl-2-iodo-5-methoxytryptamine or 2-iodomelatonin, in a dose of 20-40 mg pro die, in association with a progestinic compound. The administration is carried out for 23 days, by using an association of 2-iodomelatonin and/or melatonin and/or 2-bromomelatonin and a progestinic compound, followed by 5 days in which only 2-iodomelatonin and/or melatonin and/or 2-bromomelatonin is administered; the drug having oncostatic preventive and therapeutic properties, in mammary tumours and melanomas, characterized by the use of 2-iodomelatonin, melatonin and 2-bromomelatonin respectively with doses of 20-40 mg, 100-200 mg, 25-50 mg pro die; and the said drug having moreover antikinetosic properties, and being characterized by the use of 2-iodomelatonin in a dose pro die of 2.5 mg, melatonin, in a dose pro die of 10 mg and 2-bromomelatonin in a dose pro die of 3.5 mg, either individually and/or in association with the acetyl coenzime A-(AcCoA), in a dose of 8-10 mg pro die.