Additionally, some drugs may also be useful for the treatment of HD, such as rilmenidine [202], histone deacetylase (HDAC) inhibitors [203], CTEP (a negative allosteric modulator of metabotropic glutamate receptor 5 (mGluR5)) [204], liraglutide (a GLP-1 analogue) [205], neferine (a bisbenzylisoquinoline alkaloid isolated from the lotus seed embryo of Nelumbo nucifera Gaertn) [206], their targets are listed in Table 1. This evidence concerns the gene GRM5 and Huntington disease.