Cataracts can be caused by toxic insult (chemotherapy), nutritional deficiencies, heredity, genetic predisposition, or diabetes, as well as endogenous causes such as uveitis, retinal degeneration (PRA), and glaucoma. Referral to a veterinary ophthalmologist and possible surgical treatment is warranted, but if that is not possible then herbal support may be beneficial.
Use herbs that are high in antioxidants and that improve circulation. Botanicals such as Bilberry (Vaccinium myrtillus) may be helpful. In diabetic cataracts, flavonoids, particularly Quercetin, are potent inhibitors of aldose reductase. In a study of people with senile cataracts, a combination of Bilberry (standardized to 25% anthocyanosides; given at a dose of 180 mg twice daily) and vitamin E (100 mg twice daily) that was given for 4 months halted progression in 96% of patients compared to 76% of the control group. In a study in rats with early senile cataract and macular degeneration, the effect of Bilberry was investigated over 1.5 to 3 months. The treatment group was given a diet supplemented with 25% Bilberry extract (20 mg / kg, including 4.5 mg of antocianidin) or vitamin E (40 mg / kg). At the end of the study, more than 70% of the control rats (unsupplemented) had cataracts and macular degeneration compared to the treated group, which completely prevented impairments in the lenses and retina. The vitamin E had no significant effects but both antioxidants decreased lipid peroxides in the retina and serum of the rats. This suggests that long-term supplementation with Bilberry is effective in prevention of macular degeneration and cataracts.
Oral dose: Aqueous extract standardized to 25% anthocyanosides, 2 to 4 mg / kg TID; tincture, 1:2 to 1:3: 0.5 to 1.5 mL per 10 kg (20 pounds) divided daily.
Turmeric and Curcumin were investigated on streptozotocin-induced diabetic cataracts in rats in a placebo-controlled study. The treatment groups received 0.002% and 0.01% curcumin and 0.5% turmeric in their diets, respectively, for 8 weeks. Although neither Curcumin nor Turmeric prevented streptozotocin-induced hyperglycemia, slit lamp microscope observations indicated that these supplements delayed the progression and maturation of cataracts and the results indicate that Turmeric and Curcumin might prevent or delay the development of cataracts.
Curcumin dose: Canine, 0 to 250 mg TID; feline, 50 to 100 mg SID; dried herb, 50 to 150 mg / kg divided daily if extracted and dried; triple or quadruple dose for unprocessed herb (to maximum palatability tolerance); tincture, 1:2 to 1:3 : 1 to 3 mL per 10 kg (20 pounds) divided daily.
Ginkgo biloba was investigated in a placebo-controlled study in preventing radiation-induced cataracts in the lens after total-cranium irradiation of rats with a single radiation dose of 5 Gy. The results suggested that Ginkgo biloba is an antioxidant that protects the rat lens from radiation-induced cataracts.
Dose: Standardized extract, (50:1) 10 to 50 mg per 10 kg divided BID or TID; tincture, 1:2 to 1:3 : 0.5 to 1 mL per 10 kg (20 pounds) divided daily.
The anticataract activity of a Grapeseed extract (containing 38.5% procyanidins) was investigated in hereditary cataractous rats. The rats were fed a standard diet that contained 0% or 0.213% GSE (0.082% procyanidins in the diet (w / w)) for 27 days. Results suggested that procyanidins and their antioxidative metabolites prevented the progression of cataract formation by their antioxidative action.
Canine dose: 1 to 2 mg per kg of extract daily.
In rats with cataracts induced by subcutaneous injection of selenite, administration of aqueous extracts of green and black tea led to a retardation of the progression of lens opacity, suggesting the potential cataractostatic ability of tea.
Dose: Standardized extract containing 80% polyphenols, 25 to 75 mg / kg divided daily. Green tea can be added easily to moist food and in water (one-half to 1 cup per 10 kg per day).
Other herbs have been investigated for their protective action. In streptozotocin-induced diabetic rats, dried leaf powder of Mulberry (Morus indica L.) given at a dose of 25% of the diet for 8 weeks resulted in controlled hyperglycemia, glycosuria, and albuminuria, and it retarded the onset of retinopathy. The control rats showed the hallmarks of diabetes and developed lenticular opacity after 8 weeks of study. Evidence suggests that lutein consumption is inversely related to eye diseases such as age-related macular degeneration and cataracts in people. Lutein can be obtained from the diet in several different ways, including supplements, and some pet foods.
A crude extract of Corydalis inhibited aldose reductase, which may help prevent cataracts associated with diabetes. Oral Wheat sprout extract (dose not provided) was investigated for its effect on cataracts in dogs. Older dogs were treated for a month and the lens opacity was analyzed before and after the treatment. Results showed a reduction of 25% to 40% of lens opacity. The efficacy of Wheat sprouts in the recovery of age-related alterations and in treating age-associated pathologies is possibly due to the presence of small regulatory acid peptides, phosphoric radicals, and antioxidants.