Ginkgo biloba is used for many other indications, including improving connective tissue conditions such as haemorrhoids, common allergies, reducing the effects of exposure to radiation and to prevent some of the complications associated with diabetes. In the UK and other European countries, the cardioprotective effects of EGb 751 in myocardial ischaemia and reperfusion are currently being investigated in preclinical studies.
ADJUNCT IN CANCER TREATMENT
As a herb with significant antioxidant activity, ginkgo has been used to reduce the toxic side-effects of some chemotherapeutic drugs. Evidence from in vivo studies demonstrate protective effects against nephrotoxicity induced by cisplatin and cardiotoxicity induced by doxorubicin. Clinical trials are not yet available to determine its effectiveness in practice.
A 2005 review puts forward the case that Ginkgo biloba should be more widely used as a safe, preventative agent for reducing cancer incidence. This recommendation is based on results from numerous in vitro and experimental studies showing that ginkgo affects many factors associated with the incidence and mortality of cancer.
The recommended dose varies depending on indication and condition treated.
• Dried herb: 9-10g/day.
• 120-240 mg of a 50:1 standardised extract daily in divided doses (40 mg extract is equivalent to 1.4-2.7 g leaves).
• Fluid extract (1:1): 0.5 mL three times daily.
ACCORDING TO CLINICAL STUDIES
• Asthma: 40 mg three times daily.
• Dementia and memory impairment: 120-240 mg standardised extract daily in divided doses.
• Intermittent claudication, vertigo: 120-320 mg standardised extract daily in divided doses.
• Prevention of altitude sickness: 160 mg standardised extract daily starting 5 days prior to ascent.
• Sexual dysfunction associated with antidepressant drugs: 200 mg standardised extract daily.
• Vitiligo: 120 mg standardised extract daily.
Although some studies report positive effects after 4-6 weeks’ continual use, a trial of at least 12 weeks is recommended in chronic conditions.
Tolerability in 98% of the clinical studies is good or very good. In a few cases (less than 0.001 %), gastrointestinal upset, headaches and dizziness were reported. It does not appear to alter heart rate and blood pressure, change cholesterol and triglyceride levels or increase intraocular pressure in clinical studies.
Rare case reports of subarachnoid haemorrhage, subdural haematoma, intracer-ebral haemorrhage, subphrenic haematoma, vitreous haemorrhage and postoperative bleeding have been documented.