There is emerging scientific interest in the use of Vitamin B3 (Niacin), particularly in the form of nicotinamide, for supporting or potentially treating glaucoma. Glaucoma is a group of eye conditions characterized by damage to the optic nerve, often associated with increased intraocular pressure and retinal ganglion cell loss. Recent preclinical research in animal models has shown that nicotinamide supplementation can protect retinal ganglion cells from degeneration and improve mitochondrial function, which is thought to be relevant in glaucoma pathology. Notably, a 2017 study in mice by Williams et al. published in Science demonstrated that high-dose nicotinamide prevented glaucoma development in a mouse model.

In humans, evidence is still preliminary but promising. A small pilot clinical trial (2019, Hui et al., Clinical & Experimental Ophthalmology) found that high-dose nicotinamide (up to 3 grams/day) improved inner retinal function in patients with glaucoma over a 12-week period, as measured by electroretinography. However, these studies are early-phase and involve relatively small numbers of participants and short durations. There are no large, long-term randomized controlled trials yet confirming niacin as a definitive treatment for glaucoma.

In summary, while there is scientific rationale and preliminary evidence to support further research, the strength of evidence is currently limited (rated 2/5) and Vitamin B3 should not be considered a proven therapy for glaucoma at this time.