Nicotinamide Supplementation in Glaucoma

Inclusion Criteria: * Patients aged ³ 21 years, with definitive, treated POAG, PACG including normal tension glaucoma, PDG, PXFG in one or both eyes. * Best-corrected visual acuity equal or better than 6/18 * Reproducible visual field defect due to glaucoma (3 contiguous points at less than 5%) and severity of visual field loss, MD between -2 and -18 dB. This range includes people with moderate disease which optimises detection of progression. * Patients must have at least two prior 24-2 VF tests which meet \<16% FP and \<21% fixation loss. * Previous selective laser trabeculoplasty is acceptable (IOP-lowering laser treatment) if ³ 3 months prior or filtering surgery \>6 months previously. * Normal liver function tests. * Those taking NAM already will undergo a 1-month washout period bef Exclusion Criteria: * Patients with active liver disease or end stage renal failure. * Active use of allopurinol, carbamazepine, or primidone. * Visually significant cataracts (example, likely to require surgery within 2 years). * Cataract surgery in the last 3 months or glaucoma filtration surgery in last 6 months. * Conditions that may cause non-glaucomatous visual field defect (for example, severe ptosis, cerebrovascular accident, prior panretinal photocoagulation, and other retinal or central nervous system diseases). * Not able to complete study (for example, concurrent severe systemic disease). * History of cancer in the last 5 years. * Unable to give consent. * Inability to tolerate or take nicotinamide and/or pyruvate. * Women of Child Bearing Potential, pregnancy or lactation. * History of Hypotension * Blood Pressure measurement of less than 90/60(