This story illustrates why it is better to consult a knowledgeable herbalist than leave it to suppliers’ marketing and sales information.
Some years ago when I first got interested in medicinal plants and had begun a course of study, I purchased a bottle of Ginkgo extract. Inside the bottle were dry capsules containing extract of leaves of the plant species Ginkgo biloba, also known as the maidenhair tree. I had read somewhere that Ginkgo was a student’s special remedy, as it would boost brain power and memory, and as I had begun to feel somewhat sluggish some mornings, a remedy that could provide a boost to my cognitive state was worth considering. Furthermore, I had begun to find strong coffee – the usual morning remedy – had a sting in its tail in that it could make me feel somewhat reactive and could also slightly unsettle the stomach.
I took one of these Gingko capsules one morning after breakfast and waited for it to take effect. A student friend told me I probably wouldn’t feel a thing, as herbs like that took several weeks to ‘kick-in’. “Really?”, I said, more than a little disappointed that this wonder herb could not deliver an instant boost to a waning attention span and sluggish early morning, short term memory. Not long after this, a piercing pain struck through my forehead and right temple. Was this the healing action of a medicinal plant I asked myself – or a head cold about to explode through my sinuses?
The head cold never erupted and a few days later I took another Ginkgo capsule, and suffered a similar pain in my forehead. I repeated it a third time and although the pain was not as severe the first time it was there and sufficiently for me to conclude that it was the Gingko extract and not anything else. I left the bottle to collect dust and even tried a capsule again some years later from that same bottle and sure enough the same ‘side effect’ got me. Not surprisingly, I came to the conclusion that Gingko and I did not mix too well. I did not write the herb off completely, however, as I had read plenty about it and knew it could help thousands if not millions of people who have poor circulation. It had also occurred to me that the high dose of the dry extract might have been too high for my particular case.
Now, as a qualified practising herbalist, I have given people tincture of gingko and mixed it with other liquid herbal extracts to provide combinations that fitted their particular individual requirements. For example, Gingko is useful in combination with Cayenne for Raynaud’s disease, where small arterioles shut down in the hand, causing them to turn blue with cold. These two herbs can also people with weak peripheral circulation in their legs.
I had also learnt that the quality of an extract matters, in that contaminants can spoil preparations, and the source plant itself may have grown on a plot where it could not generate the active constituents in sufficient qualities to make an effective herbal drug, or it might be a sub-species or variety that does not contain the active constituent chemicals to the same degree that the medicinal type does. 
At a seminar, I was also reminded that the dose of Gingko extract needs to be high to achieve the benefits for the circulation to the brain and elsewhere. I was told that a concentrated dry extract in either a tablet or capsule was the best way to achieve such a high dosage, as with tinctures you would have to swallow too much alcohol (though in theory these could be made with vinegar or glycerine, in practice liquid extracts are usually made with alcohol). Each capsule recommended by the seminar contained the equivalent of 3 grams of dry weight of leaf, standardized to 3.6 mg of gingkolides (important active constituents) and the top dose was three of these taken three times daily.
As a result of attending this seminar, decided to trial the recommended Gingko tablets. I have taken just one tablet a day for the past week and have already noticed small improvements. But the most important discovery has been that a high dosage Gingko extract does not necessarily give me a headache! Despite the fact these latest tablets were of a higher dosage than the ones I had taken all those years ago, there was no headache, rather I felt better.
So, what are the lessons from this story? Number one is that the quality of the herbal extract is most important if you are going to obtain the benefits you seek. The supplier of the latest tablets I have taken is a high quality manufacturer of herbal medicines that carries out many chemical tests to ensure the extracts it makes contain what they should to deliver efficacy without side effects. Secondly, you can’t conclude that a plant is no good to you on the basis of one sample from one supplier, especially if their quality may not be of the highest. A third lesson is that a high dosage can deliver clinical benefits more or less straightway, even if folklore or tradition says that the plant’s medicinal extract takes weeks to “kick-in”. Lastly, if you are going to take a high dosage, you need to be sure that the herbal medicine you are taking is not contaminated and contains the beneficial constituents it is meant to, and therefore you need to rely on a herbal manufacturer of the highest quality and reputation. To obtain this you are best consulting a qualified medical herbalist, who will not only advise you on the best dose for you, commensurate with your clinical requirements, but also know the best supplier to order from. The quality supplier I have referred to does not supply to the public, only to qualified practitioners.
