B Vitamins And Their Role In The Treatment Of Glaucoma
What are the “B Vitamins”?
B vitamins are a group of chemically varied water-soluble vitamins that are often naturally found together in food. There are eight distinct vitamins that are often packaged together in supplements termed “Vitamin B Complex”
What’s Inside A Vitamin B Complex
- Vitamin B1 (thiamin)
- Vitamin B2 (riboflavin)
- Vitamin B3 (niacin or niacinamide)
- Vitamin B5 (pantothenic acid)
- Vitamin B6 (pyridoxine, pyridoxal, or pyridoxamine, or pyridoxine hydrochloride)
- Vitamin B7 (biotin)
- Vitamin B9 (folate)
- Vitamin B12 (various cobalamins such as Methylcobalamin)
Evidence that Vitamin B Can Be Used To Treat Glaucoma
At least in combination with Vitamin E and DHA, Vitamin B has been shown to improve visual fields and retinal sensitivity in patients with glaucoma.[1] Of the B vitamins, Vitamin B12 (Methylcobalamin) has the most support for its role in glaucoma treatment. Multiple studies have looked into its effect on both chronic open angle glaucoma[2] as well as normal tension glaucoma.[3] The evidence suggests that its use may slow visual field loss.
Potential Side Effects and Risks
In the dosages available in most over-the-counter multivitamins the most common side effect is a change in the color and odor of one’s urine. Thiamine, Riboflavin, Pantothenic acid, and biotin are essentially without other significant side effects when taken orally. However, high concentrations achieved from intravenous or intramuscular injection of B vitamins can be associated with significant side effects. Additionally, the following B vitamins can have significant side effects when taken orally in large doses: Vitamin B3 (nicotinamide >3000 mg/day or nicotinic acid >1500 mg/day), Vitamin B6 (pyridoxine >200mg/day), Vitamin B9, and Vitamin B12.
Potential Drug Interactions
Vitamin B12 should not be taken along with Chloramphenicol as this combination can have a detrimental effect on red blood cells.[4]
Recommended Dosage
As there are only a few studies that have looked at treating glaucoma with Vitamin B complex, the optimal dosage is not known. At least with Vitamin B12 (methylcobalamin) we have one study that demonstrated a benefit on visual field defect progression in patients with normal tension glaucoma using a daily dose of 1,500mcg (1.5mg).[5] Thus, I now recommend that my patients with glaucoma take a Vitamin B Complex as well as 1,500mcg (1.5mg) of Vitamin B12 (methylcobalamin) each day.
Where to Buy
If you are interested in B Vitamins in the treatment of glaucoma, note that Vitamin quality can vary greatly. To be certain you are getting a high quality product I would recommend you only purchase supplements such as B vitamins from a trusted brand such as Life Extension.
References
1) Cellini M, Caramazza N, Mangiafi co P, et al. Fatty acid use in glaucomatous optic neuropathy treatment. Acta Ophthalmol Scand. 1998;227(suppl):41–42.
2) Azumi I, Kosaki H, Nakatani H. Effects of metcobalamin (Methylcobal) on the visual field of chronic glaucoma – a multi-center open study. Folia Ophthalmol Jpn. 1983;34:873–878.
Ichikawa H, Shiose Y, Tanabe Y, et al. Effect of Methycobal for visual field change of glaucoma – multicenter clinical trial by controlled study. Journal of the Eye. 1988;5:617-624.
Kojima Y, Futa R, Furuyoshi N, et al. The long-term effect of mecobalamine on visual function in glaucomatous eyes. Folia Ophthalmol Jpn. 1990;41:1314-1318.
Sasaki T, Murata M, Amemiya T. Effect of long-term treatment of glaucoma with vitamin B12. Glaucoma. 1992;14:167-170.
3) Shiose Y. The efficacy of methylcobalamine against low-tension glaucoma. Folia Ophthalmol Jpn. 1988;39:750-756.
Yamazaki Y, Hayamizu F, Nakagami T, et al. Effect of peroral mecobalamine on the visual field defect in normal-tension glaucoma. Jpn J Clin Ophthalmol. 1998;52:915-919.
Yamazaki Y, Hayamizu F, Tanaka C. Effects of long-term methylcobalamin treatment on the progression of visual field defects in normal-tension glaucoma. Curr Ther Res. 2000;61:443–451.
4) Tatro DS, ed. Drug Interactions Facts. Facts and Comparisons Inc., St. Louis, MO. 1999.
5) Yamazaki Y, Hayamizu F, Tanaka C. Effects of long-term methylcobalamin treatment on the progression of visual field defects in normal-tension glaucoma. Curr Ther Res. 2000;61:443–451.
Looking for an Ophthalmologist in California?
Dr. David Richardson is taking new patients at his office in San Marino, CA., and is always willing to provide a second opinion for those who would like the peace-of-mind that such a consultation would provide.