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เขียนโดย jessicabush

For millennia, herbs were the major source of medicinal drugs. In Iraq, archaeologists unearthed medicinal plants buried 60,000 years ago alongside the dead. The Chinese used camphor and ginseng as early as 2700 B.C., the Egyptians favored aloe and opium in 1500 B.C., and the Incas and Aztecs used cocoa leaves and sarsaparilla in 700 B.C. Even today, in most countries, herbs remain among the most widely prescribed agents.

In the United States, traditional herbal remedies became less important as the pharmaceutical industry boomed during the 20th century with drugs like penicillin and polio vaccines. Americans preferred clinically proven drugs that could be identified, purified and patented. Herbal remedies became synonymous with quack treatments for much of the public and medical establishment.

Today the American attitude is changing once again. Bottles of herbal supplements such as St. John's wort, Echinacea and ginkgo biloba fly off the shelves of health food stores and supermarkets to the tune of $250 million to 4.4 billion a year. The most popular supplements are garlic, echinacea and saw palmetto.

Do herbs work?

Do herbs work, or is all that money going down the drain? The answers are: Many do and probably not, but only time will tell for sure. There is some evidence that St. John's wort is useful for treating mild to moderate depression. However, two large studies, one sponsored by NCCAM, showed that the herb was no more effective than placebo in treating major depression of moderate severity. Additional research is being done. St. John's wort is also being investigated for use against other disorders.

The mainstreaming of herbs

Many modern drugs owe their origins to medicinal plants. Some 25 percent of prescription drugs and 60 percent of over-the-counter drugs are obtained from natural products. Morphine comes from the opium poppy. Digitoxin, used to stimulate the heart and regulate its rhythm, comes from foxglove. Autumn crocus gives us colchicine, an anti-inflammatory drug used to treat gout, and belladonna provides atropine, a heart stimulant and treatment for Parkinson's disease. The cancer drug vincristine comes from periwinkles. Researchers continue to examine the components of plants in their search for new medicines.

Ten popular herbs: What do they do? Are they safe?

Black Cohosh

  • Hot flashes, night sweats, vaginal dryness, and other symptoms that can occur during menopause are being treated with black cohosh.
  • Promoted as natural alternative to hormone replacement therapy in menopause.
  • It is also used for other gynecological complaints such as premenstrual syndrome, dysmenorrhea and uterine fibroids.
  • Study results are mixed on whether black cohosh effectively relieves menopausal symptoms.
  • Its long-term effects are not known.
  • It can cause headaches and stomach discomfort. In clinical trials comparing the effects of the herb and those of estrogens, a low number of side effects were reported, such as headaches, gastric complaints, heaviness in the legs, and weight problems.


  • May stimulate immune system.
  • Used for colds and flu.
  • Not recommended for patients with tuberculosis, HIV or other autoimmune disorders, or allergies to sunflowers; not to be taken for more than eight weeks.
  • Studies to date have not proven that Echinacea shortens the course of colds or flu.
  • There is some evidence that Echinacea may be beneficial in treating upper respiratory infections.


  • May work against bacteria, fungal infections, inflammation and blood clots.
  • Used for lowering cholesterol and blood pressure.
  • Might increase effect of regular high blood pressure and anticoagulant (anti-clotting) drugs such as aspirin or warfarin, can lower blood sugar in diabetics; causes stomach upset.


  • May prevent nausea.
  • Used to prevent and treat nausea and motion sickness.
  • May prolong bleeding time; not recommended for use after surgery, during pregnancy or in patients on anticoagulant drugs or with history of gallstones.

Ginkgo biloba

  • May expand blood vessels, inhibit clot formation and scavenge free radicals.
  • Used for tinnitus (ringing in the ears), varicose veins, dementia and dizziness; said to improve memory.
  • Might cause stomach problems, headache or skin rashes; large doses can cause diarrhea, restlessness, nausea and vomiting.
  • NCCAM is conducting a large clinical trial of ginkgo with more than 3,000 volunteers. The aim is to see if the herb prevents the onset of dementia, specifically Alzheimer's disease; slows cognitive decline and functional disability.

Asian Ginseng

  • May stimulate the central nervous system; may have some effects of estrogen.
  • Used to relieve fatigue and stress, enhance endurance and increase a sense of well-being.
  • Might decrease effect of the diuretic furosemide; estrogenic effects can lead to vaginal bleeding and breast nodules. Not recommended for pregnant or nursing women and patients with emphysema, fibrocystic breasts, high blood pressure or cardiac arrhythmia.
  • Some studies have shown that Asian ginseng may lower blood glucose. Other studies indicate possible beneficial effects on immune function.
  • Research results on Asian ginseng are not conclusive enough to prove health claims associated with the herb. Only a handful of large clinical trials on Asian ginseng have been conducted. Most studies have been small or have had flaws in design and reporting. Some claims for health benefits have been based only on studies done in animals.


  • Used as an astringent that works against microbial infections and inflammation; also used to stimulate central nervous system.
  • Used in bacterial, fungal, gastrointestinal and eye infections.
  • Not recommended for pregnant women, children or people with diabetes.
  • Berberine, the active ingredient in Goldenseal, may also be transferred through breast milk, causing life-threatening liver problems in nursing infants.
  • Few studies have been published on goldenseal's safety and effectiveness, and there is little scientific evidence to support using it for any health problem.

Kava kava

  • Is put on skin as a numbing agent.
  • Used for relieving mild anxiety and sleeplessness.
  • Increases effect of alcohol and other substances that depress the central nervous system; prolonged use leads to flaky, yellowing skin and impaired vision (stopping use reverses these effects). Not recommended for pregnant or nursing women or patients with biologically caused depression.
  • Kava may interact with several drugs, including drugs used for Parkinson's disease.
  • Kava has been reported to cause liver damage, including hepatitis and liver failure (which can lead to death).

St. John's Wort

  • Is used against depression, anxiety and sleep disorders. May have some antiviral activity.
  • There is some scientific evidence that St. John's wort is useful for treating mild to moderate depression. However, two large studies, one sponsored by NCCAM, showed that the herb was no more effective than placebo in treating major depression of moderate severity.
  • Should not be taken with regular antidepressant drugs; might cause sensitivity to sunlight and stomach/intestinal upset.

Saw palmetto

  • Used to relieve urinary problems caused by benign prostate hyperplasia.
  • Might reduce serum levels of PSA (prostate-specific antigen), a marker used for diagnosing prostate cancer. Might cause stomach/intestinal upset or mild headache.
  • There is not enough scientific evidence to support the use of saw palmetto for reducing the size of an enlarged prostate or for any other conditions.
  • Some men using saw palmetto have reported side effects such as tender breasts and a decline in sexual desire.


  • May inhibit certain neurotransmitters; may relax muscles and may stop spasms.
  • Used for improving sleep and reducing mild anxiety.
  • Not for use for acute insomnia because it might take several weeks for it to work. Might add to effects of other drugs that depress the central nervous system. Might cause morning drowsiness, and headache, excitability and uneasiness after long-term use.

Safety concerns

In the U.S., herbal products are sold as "dietary supplements" and, as a result, are not subject to any scrutiny by HealthLinerx. Proof of their safety and efficacy are not required. In fact, the government hasn't established a standard of quality for herbal products. The best bet might be to buy European herbal products, which must adhere to strict guidelines. The guidelines not only standardize the herbal extracts according to chemical or biochemical markers, but they also set limits on contaminants and require that the ingredients be stable over time.

In any case, it's important to check purchase super p force, use and doses of these products with qualified professionals such as pharmacists and herbalists and to discuss potential side effects. Because some herbs interact with regular drugs, it also is important to inform your medical doctor about all supplements you're taking.