What is Bilberry?
Bilberry is an herb whose fruit has been used in human herbal medicine for centuries. Bilberry, related to blueberry, has antioxidant properties, and is most commonly taken internally in people to help with disorders of the eyes including macular degeneration (deterioration of part of the retina or back of the eye) and cataract formation. Interestingly, however, no trials on the efficacy of Bilberry in the treatment of eye disorders have been performed to date. Bilberry is also considered able to improve night vision, but studies have been inconclusive. The ability of Bilberry to increase vision may depend on the dose used and where the plant is from.
Of far more potential interest to veterinarians is relatively new research of Bilberry's effects on circulation. The flavonoids of Bilberry have long been known to improve circulation, presumably by reducing capillary fragility. For these reasons, Bilberry has been used in humans to improve retinal blood flow and address peripheral circulation disorders such as bruising and varicosities (e.g. varicose veins). More recently, however, the flavonoids have been found able to strongly inhibit the formation of hemangioma, resulting in a reduction of tumor size by about 50 percent in one human study. These results suggest Bilberry extract may hold promise in treating vascular (blood vessel) tumors in dogs, such as hemangiosarcoma. An anti-neoplastic (i.e. anti-tumor) effect against other cell types has also been demonstrated, due in part to Bilberry's content of anthocyanins. Anthocyanins are a powerful antioxidant known to play a significant role in inhibiting tumor formation due to their ability to scavenge free radicals which might otherwise damage DNA and promote neoplasia (see article on Antioxidants).
Why recommend administration of Bilberry to my pet?
In people, Bilberry has been used for the treatment of diarrhea, eye problems relating to impaired retinal blood flow, and problems associated with peripheral perfusion (blood flow to the extremities). In pets, it is often prescribed for conditions which may respond to the use of antioxidants. Eye diseases including cataracts and retinal degeneration may respond to Bilberry supplementation, but controlled studies are lacking. Bilberry may prove effective in the treatment of hemangiosarcoma (cancer of blood vessels) in dogs.
How much experience is there with the use of Bilberry in pets?
Bilberry has been recommended for pets based upon experience in people. Its use in pets is very recent.
What species of animals are being treated regularly with Bilberry?
Generally dogs and cats are treated with supplements containing Bilberry and other antioxidants.
How much research has been conducted on this supplement?
Both in vitro laboratory testing and research with human subjects have been conducted, but there are no controlled studies in pets.
How successful is Bilberry?
Bilberry is unlikely to be effective for progressive retinal atrophy (PRA or deterioration of the blood vessel and nerve-rich back of the eye) in dogs, since the problem does not arise from poor blood flow, but creates it instead. Bilberry may be of far more benefit for dogs in the treatment of hemangiosarcoma (blood vessel cancer), but this use is currently purely speculative. Bilberry can be expected to benefit any condition that would benefit from antioxidant therapy, given Bilberry's content of potent flavonoids.
How safe is Bilberry?
Bilberry is very safe and considered non-toxic. Essentially, it can be considered a food.
Where do I obtain Bilberry and do I need a prescription?
Your veterinarian may have preferred supplements that he or she will recommend. Pet owners are cautioned against buying supplements without knowledge of the manufacturer, as supplements are not highly regulated and some supplements may not contain the labelled amount of ingredients. A prescription is not needed for Bilberry.
Based on material written by Steve Marsden, DVM ND MSOM LAc DiplCH AHG, Shawn Messonnier, DVM and Cheryl Yuill, DVM, MSc, CVH and modified with permission from Lifelearn Inc.
© Copyright 2004 Lifelearn Inc.
