The invention concerns the therapeutic use of tricyclic salts and their pharmaceutically acceptable salts having the general formula: in which: A is either a sulfur atom, an oxygen atom, or an R3N radical where R3 is a hydrogen atom, a C1-C5 alkyl radical, or a substituted or unsubstituted aromatic ring, or a substituted or unsubstituted heteroaromatic ring. R1 is either a C1-C5 alkyl radical, or an R4NH radical where R4 is a hydrogen atom, a C1-C5 alkyl radical, or a substituted or unsubstituted aromatic ring, or a substituted or unsubstituted heteroaromatic ring, or an aromatic ring that may or may not be substituted by one or more acceptor or donor groups, or a heteroaromatic ring having one or more heteroatoms, which may or may not be substituted by acceptor or donor groups. R2 is a hydrogen atom, halogen atom, a C1-C5 alkyl radical, an oxygen atom that may or may not be substituted by a C1-C5 alkyl radical, or an NR5R5, radical where R5 and R5, are, independently of each other, a hydrogen atom, an oxygen atom or monovalent C1-C5 organic radicals.