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II.2. Прочтите текст а и дайте письменные ответы на следующие вопросы.

        1. What drugs derived from plants can you name except those mentioned in the text?

        2. Why is testing of herbs for safety and potency not obligatory in the USA?

        3. Who and when can remove the herbs from the market in America?

        4. Why should not the herbs be used indiscriminately?

        5. What hazards do herbs present?

        6. When are the herbal ingredients more potent?

        7. Which parts of the herbs are commonly used as remedies?

        8. In what forms can the herbs be found on the shelves of pharmacies and drugstores?

Text a Herbs

Many of the drugs available on the market are derived from plants. Some of those include aspirin, atropine, belladonna, digoxin, ephedrine, ergotamine, opium, podophyllum, quinidine, reserpine, senna, taxol, vinblastine and vincristine.

Herbs are also derived from plants. However, herbs are not considered drugs by the Food and Drug Administration (FDA) in the USA. While the federal pharmacy law requires that pharmaceutical companies test drugs for safety and potency before marketing, testing of the herbs is not mandatory. Herbs are considered dietary suppmements, and dietary supplements do not have to be standardized. The Secretary of State and Human Services may remove a supplement from the market only when it has been reported to be hazardous to health. The following statement is required on the product label: “This product has not been evaluated by the FDA. It is not intended to diagnose, treat, cure, or prevent”.

Many people believe that the healing properties of herbs are just as effective as those of drugs, but without side effects. Herbs do perform many healing functions in the body but they must be used appropriately, not indiscriminately. One should remember that there are highly poisonous medicinal plants, and some are deadly, especially if used for long periods of time. Herbs can be very potent, so it is important to regulate their dosage. Most herbs sold over-the-counter are too strong.

It is of interest to note that in many industrialized countries today, herbs are prescribed by physicians and prepared and sold through neighbourhood drugstores. (In fact, in countries where acces to hospitals and doctors is limited, herbal remedies are the only form of medicine).

It is important to point out that qualified herbalists use herbs with great care. Since herbs contain active ingredients, one should be aware that some of these substances may interact negatively with prescribed medications. Some herbs are considered unsafe for human consumption. Carcinogenic herbs include borage, coltsfoot, comfrey and life root. Hepatotoxic herbs include germander and life root. Pokeroot may be fatal in children.

High doses of liquorice for long periods may cause pseudoaldosteronism, a condition that may include headache, lethargy, sodium and water retention, hypokalemia, high blood pressure, heart failure, and cardiac arrest.

Potentially safe herbs include black cohosh, echinacea, feverfew, garlic, ginkgo, ginger, ginseng, St. John’s wort, and valerian. Still, while using these, it is always wise to consult a health professional or a herbal concerning their safe administration. As a general guideline, one should remember that the pleasant-tasting herbs are potentially less toxic than the bitter-tasting ones. Certain herbs should be used only while healing, and not longer than six months at a time. Also, most herbal ingredients are more potent when taken from freshly picked herbs.

The fresh leaves and roots of herbs can be used in their natural form, or they can be found in tablet form, in capsules, medicinal beverages, powders, extracts tinctures, creams, lotions, balms, ointments (salves), and essential oils. Bark can be found in reduced form, including bark pieces and powders.

All roots and bark are fungicidal and bactericidal, otherwise pathogens would destroy them in the ground. Roots, bark and some herbs will retain their medicinal value for years when thoroughly dried and kept dry and protected from light.