An analysis of over-the-counter products show not all AMD-targeting supplements match the recommended dosage from the National Institutes of Health.
Commercially available and clinically recommended products with vitamin supplements relevant to treatment of age-related macular degeneration (AMD) may not be consistent in neither price nor availability to patients across the globe, according to findings from a multinational study.
In new research from a team of Australia investigators, products containing vitamin C and E, zinc, copper, lutein and zeaxanthin are not available at fixed regimens nor costs across Australia and North America. The regimen, which was previously outlined by the National Eye Institute’s (NEI) Age-Related Eye Disease Studies (AREDS 2) results, are as follows:
“If you have late AMD in only 1 eye, AREDS 2 may slow down the progression of AMD in the other eye,” the NEI states. “If you already have late AMD in both eyes, AREDS 2 supplements probably won’t help. But low vision resources can help you make the most of your remaining sight.”
Investigators led by Ye Li, MBChB, of the department of ophthalmology at Princess Alexandra Hospital, sought to review available products for AMD, as well as those that mirror the AREDS 2 “recipe.”
They conducted an electronic review of AMD supplements available over the counter in pharmacies and relevant websites across regions of Australia, the US, UK, and Canada. The team additionally reviewed supplement product doses, formulations, and costs, while additionally including all products containing AREDS 2 ingredients.
Their final analysis included 66 reviewed products, 43 (65.2%) of which contained all ingredients from AREDS 2. Among those, only 20 (46.5%) contained all 7 ingredients at ≥100% recommended doses. The remaining 23 (53.4%) contained ≥1 ingredient at a lower dose than recommended.
Regarding availability, 7 (35%) AREDS 2 products were only available online, and the remaining 13 were available in pharmacies as well. Formulations varied from 23 capsule products, 9 soft-gel products, 7 tablet products, 2 capsule/powder products, 1 powder product, and 1 product requiring both a tablet and soft gel.
Costs for the products additionally ranged widely, from $0.12 to $6.72 mean Australian dollars for daily consumption.
“Commercially available products for ARMD are variable in price and resemblance to the evidence-based AREDS 2 formula,” investigators wrote. “Clinicians should be aware of this information to assist in counseling patients with ARMD.”
The study, “An analysis of evidence-based vitamin supplements for age-related macular degeneration,” was published online in Clinical & Experimental Ophthalmology.