The invention relates to derivatives of indole-3-carboxamide having general formula (I): ##STR00001## wherein: R.sub.1 represents a C.sub.3 C.sub.10 alkyl, a C.sub.5 C.sub.10 carbocyclic radical that is unsubstituted or substituted one or more times with a methyl group; R.sub.2 represents a hydrogen atom or a (C.sub.1 C.sub.4)alkyl group; R.sub.3 represents a halogen atom or a (C.sub.1 C.sub.4)alkyl group; R.sub.4 represents a hydrogen or halogen atom or a (C.sub.1 C.sub.4)alkyl group; R.sub.5 represents a (C.sub.1 C.sub.4)alkyl group or a trifluoromethyl; X represents a sulfur atom, an --NHSO.sub.2-- group or an --SO.sub.2-- group; and n is equal to 2 or 3. The invention also relates to a method of preparing the aforementioned derivatives and to the application of same in therapeutics.