The medical treatment of glaucoma has undergone significant development in recent years. Research in this field is focused on improving pre-existing drugs and on the development of new molecules. In relation to commercial drugs, there is a trend to improve local tolerance, using less toxic preservatives as in the case of sofZIA in travoprost, and eliminating the preservatives as in tafluprost. The development of new, fixed combinations of commercial drugs could also enhance their administration and therapeutic compliance. There is also intense research activity in the search for new therapeutic groups for glaucoma treatment. Calcium channel-blockers such as lomerizine do not seem to affect systemic hypotension, while topical calcium-blockers like flunarizine and iganidipine are also under research. Endothelin 1 antagonists such as sulfisoxazole and bunazosine could be also useful in the treatment of glaucoma. In the renin angiotensin system, angiotensin (1-7) and olmesartan are under investigation for use in glaucoma patients. Trabecular drugs such as Rho-kinase inhibitors could be effective on the pathogenic mechanism of primary open angle glaucoma. Finally, topical mifepristone, an antagonist of glucocorticoid receptors, is under evaluation for corticosteroid-induced elevated intraocular pressure (Arch Soc Esp Oftalmol 2009; 84: 491-500).