Plants adverse side effects

A frequently cited example of an important natural-product-derived drag is the neuromuscular blocker d-tubocurarine, derived from the South American plant curare, which was used by South American Indians as an arrow poison (see Chapter 26). Tubocurarine led to the development of decamethonium, which, although structurally dissimilar to tubocurarine, was nevertheless synthesized based on the then prevalent presumption that tubocurarine contained two quaternary nitrogens. Similarly, synthetic local anesthetics, such as lidocaine, benzocaine, and dibucaine, were synthesized to mimic the nerve-blocking effect of cocaine, a natural alkaloid obtained from the leaves of Coca eroxylum, but without the adverse side effects that have led to its abuse. 

The chemical control of insect pests dates back thousands of years. The earliest insecticides were inorganic compounds of copper, lead, and arsenic, as well as some naturally occurring organic compounds such as nicotine (Fig. 7.30a). Few of these first-generation insecticides are in use today because of their adverse side effects on plants, animals, and humans. 

Of course, if the substances work, do not have debilitating and life-threatening side effects, and can be mass-produced, who cares There is an argument also for using the pure chemical, in that some of the myriad biochemicals or phytochemicals in plants or herbs are additional sources of potentially adverse side effects.)... 

There is certainly a cautionary note sounded here, given the array of questionable chemical compounds in the various plants, and the adverse side effects. One can wonder who all tried out each herbal in the first place, for whichever and whatever ailments. Do any of these herbs act against cancer And how reliable is the information from hearsay or folklore This brings up the matter of regulation and standardization, a not always welcome idea. In Germany there are higher standards for the formulation of herbs, although this is not so much the case in the United States. 

Very possibly, however, inhibitors for the previously mentioned enzymes may exist in the plant world, as distinguished from synthetic chemicals. And among these plant snbstances there will perhaps be some that do not have toxic or adverse side effects. 

While the pesticides control pest infestation and disease, they can adversely affect the plants and the environment via ground water contamination, besides causing adverse side effects in humans. This has led to regulations by the EPA in the United States to curtail the use of pesticides that leach into the ground water. Triazines, a group commonly present in pesticides, have antibacterial and anti-protozoan activity, and are used in the production of atrazine, which is a controversial weed-control chemical. 

Significant inhibitory effectiveness against representatives of B and Y pol families is demonstrated for natural plant gallotaimin penta-O-galloyl-beta-o-glucose (PGG) that has been shown to inhibit the in vivo growth of several types of tumors without evident adverse side effects [111-113]. 

A dietary supplement may be safe when taken in the recommended doses but may become dangerous in higher doses. However, patients may develop side effects even when ingesting recommended doses. Adverse reactions may be due to allergic reactions, dietary supplements containing toxic substances, mis-identification of plant, mislabeling of plant, natural toxic substances such as pyrrolizidine alkaloids in comfrey, unnatural toxic substances such as heavy metals, or pesticides. 

Compounds with different structures but with the same therapeutic activity isolated from different plant species act as active moieties for the treatment of particular diseases. Some of these compounds have been abandoned due to toxicity but these compounds apparently do not cause serious adverse effects. Some of these active principles originate from edible plants and their inclusion in the diet would undoubtedly be of some value because of their hypocholesterolemic potential. Several phytoconstituents including inulin, pectin, gugglu lipids, flavonoids, ginkoloids, saponins, tannins, and others obtained from various plant sources have proven hypolipidemic potentials as has been further explained in Tables I and II. The chemical structures of a few potential phytoconstituents with hypolipidemic activity are shown in Figure 2. It is hoped that as new additions are made to the list of these active compounds causing only minimum untoward side effects, these naturally... 

Herbal substitutes for dru [s of abuse A variety of herbal mixtures are offered for sale in magazines, on the internet and in so-called smart , eco or head shops. Many are marketed as herbal Ecstasy and the plants included in the formulations include Yohimbe bark, Kava-Kava (Piper methysticum),Y-3 e.emi, Hops, Jaborandi and Alisma. One product contains Kava-Kava, Guarana, Uva Ursi and Cascara bark. Many of the products sold as herbal Ecstasy contain either Ephedra sinica (Ma huang) or the Indian plant Sida cordifolia which both contain the alkaloid ephedrine (see R03c, Chapter VI). Other alkaloids may also occur, such as pseudoephedrine, norephedrine and norpseudoephedrine. The side-effects of ephedrine include tachycardia, anxiety, insomnia and arrythmias and a hypotensive crisis may develop if monamine oxidase inhibitors are also taken. Many adverse reactions and more than 20 deaths have been attributed to ephedrine and Ephedra consumption. Research conducted in the US shows that the daily intake of some Ephedra products would give ephedrine levels well above the recommended therapeutic doses. 

German chamomile or wild chamomile Matricaria recutita) is a member of the Asteraceae plant family and owes its popularity to various properties, which include confirmed anti-inflammatoty, antibacterial and antispasmodic activities. As a consequence, it is used against the common cold, stomach aches and skin inflammations. Despite its widespread use, very few adverse effects have been reported, and only some of these side effects are allergic in nature. So then, why is there so much talk about chamomile and allergies ... 

A related plant, wormwood Artemisia absinthium), gained an adverse reputation due its thu-jone content and mutual side effects associated with absinthism. It is widely distributed in Europe and introduced also in other continents. The composition of the essential oil has been studied by several authors and highlighted that large amounts of thujones are representative only for one of the... 

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