GINKGO HAS A NUMBER OF IMPORTANT CHEMICAL COMPONENTS, INCLUDING FLAVONOID GLYCOSIDES INCLUDING PROANTHOCYANIDINS AND QUERCETIN (GINKGO EXTRACT IS STANDARDIZED TO 25 PERCENT FLAVONOID GLYCOSIDES), GLUCOSE, RHAMNOSE, AND TERPENES (GINKGOLIDES AND BILOBALIDE.
In traditional Chinese herbology, tea made from ginkgo seeds has been used for numerous problems, most particularly asthma and other respiratory illnesses. The leaf was not used. But in the 1950s, German researchers started to investigate the medical possibilities of ginkgo leaf extracts rather than remedies using the seeds. Thus, modern ginkgo preparations are not the same as the traditional Chinese herb, and the comparisons often drawn are incorrect.
Ginkgo is known for a number of medicinal benefits. By inhibiting platelet activating factor (PAF), ginkgo inhibits platelets from forming clots. Because of this and the ability of ginkgo to strengthen blood vessels, many doctors use it in older pets prone to cognitive dysfunction (as it has been recommended for Alzheimer’s patients).
Ginkgo also stabilizes cell membranes and scavenges free radicals, especially in the nervous system. As a result, ginkgo can be tried on pets with any type of nervous system disease, such as seizures, incontinence, deafness, and behavioral disorders.
Gingko is also recommended for pets with kidney disease, and is often combined with hawthorn for this condition.
The scientific record for ginkgo uses in people is extensive and impressive. Numerous studies have found ginkgo extracts can improve circulation. We don’t know exactly how it does this, but unknown constituents in the herb appear to make the blood more fluid, reduce the tendency toward blood clots, extend the life of a natural blood vessel-relaxing substance, and act as an antioxidant. However, ginkgo’s influence on mental function may have nothing to do with its effects on circulation.
In the past, European physicians believed the cause of mental deterioration with age was reduced circulation in the brain due to atherosclerosis. Since ginkgo can improve circulation, they assumed ginkgo was simply getting more blood to brain cells and thereby making them work better. However, the contemporary understanding of age-related memory loss and metal impairment no longer considers chronically restricted circulation the primary issue. Ginkgo (and other drugs used for dementia) may instead function by directly stimulating nerve-cell activity and protecting nerve cells from further injury, although improvement in circulatory capacity may also play a role.
Studies have verified both in people with Alzheimer’s and those without, are helped by treating with ginkgo.
The bioflavonoids in ginkgo may inhibit histamine release from mast cells and decrease the production of chemicals which promote inflammation including leukotrienes. Ginkgo also contains terpene molecules called ginkgolides. These antagonize PAF, which is an important chemical produced by the body that causes inflammation and allergies. In double-blind studies in asthmatic people, the anti-asthmatic effect of orally administered ginkgolides has been shown to improve respiration. High doses of ginkgo extract were needed to achieve this effect.
The extensive research on people may also be applicable to pets.
The standard dosage of ginkgo in people is 40 to 80 mg three-times daily of a 50:1 extract standardized to contain 24 percent ginkgo-flavone glycosides.
Do not use Ginkgo biloba in animals with blood-clotting disorders. Do not use in pregnant animals.
Contact with live ginkgo plants can cause severe allergic reactions, and ingestion of ginkgo seeds can be dangerous. Extremely high doses have been given in animals for long periods of time without serious consequences. Safety in young children, pregnant or nursing women, or those with severe liver or kidney disease, has not been established. The same precautions may apply in pets. Ginkgo may cause diarrhea, nausea, or restlessness in excessive doses.
Because of ginkgo’s blood-thinning effects, some experts warn that it should not be combined with bloodthinning drugs such as Coumadin (warfarin), heparin, aspirin, and other nonsteroidal medications, and use of such drugs was prohibited in most of the double-blind trials on ginkgo. It is also possible that ginkgo could cause bleeding problems if combined with natural blood thinners, such as garlic and high-dose vitamin E. There have been several case reports in highly regarded journals of subdural hematoma (bleeding in the skull) and hyphema (spontaneous bleeding in the anterior chamber of the eye) in association with ginkgo use in people. As a precaution, do not use in pets with bleeding disorders, pets scheduled for surgery (refrain from us at least one week before and ne week after surgery), and those taking medicines that interfere with blood clotting.