Summary Herbal Medicines: Possible Risks and Benefits

INTRODUCTION The consumption of herbal medicines is increasing steadily throughout the world as an alternative treatment for alleviating a number of health problems including heart diseases, diabetes, high blood pressure and even certain types of cancer. In India use of herbal drugs is much more because of their easy accessibility. Unlike drugs, herbal products are not regulated for purity and potency .There are neither studies on their effectiveness nor control over the quality and safety of these preparations. As per Food and Drug Administration mandates, only medicines have to be proven to be safe before being released into market. Herbal products do not fall under the category of medicine as long as they are not marketed for the prevention of any disease. Herbal drugs are considered as 'food integrators and readily available in the market without prescription. The major driving force for the use of herbal drugs is the perception that ‘they are safe because they are natural and have fewer side effects than prescription drugs'. However, various studies and researchers have high lightened their possible side effects, if taken irregularly, in excessive amounts or in combination with some medicines1. A common problem with herb use is that people do not take into consideration how they may interact with any prescription drug American Journal of Phytomedicine and Clinical Therapeutics they are taking, or with each other. Interaction between drugs and herbs can result in unexpected concentration of drugs and also cause undesired effects. Sometimes the use of commonly used herbs with prescription medicines become big barrier for the diagnosis of certain diseases as people do not inform their physicians about their consumption. The aim of this paper is to highlight the uses and side effects of some selected below mentioned herbal drugs so that these may be used safely. A tabular presentation of uses and adverse effects of selected eleven herbal drugs is given in table1. ALOE VERA There are about 400 species of aloe. Among them, particularly Aloe vera has been widely used in phytomedicines. The botanical name of Aloe Vera is Aloe barbadensis miller. It belongs to Asphodelaceae (Liliaceae) family, and is a shrubby or arborescent, perennial, xerophytic, succulent; pea- green colour plant. Benefits The Aloe Vera plant has been known and used for centuries for its health, beauty, medicinal and skin care properties. Phytomedicine describes aloe as an herb which has anti-inflammatory, antiproliferative and anti-aging effects. The Greek scientists regarded Aloe Vera as the universal panacea. The Egyptians called Aloe “the plant of immortality”. Also, aloe has been purported to have positive effects on wound healing, recovery from burn injury, cell growth and immune modulation. Risks But, in recent years several cases of aloe-induced hepatotoxicity were reported. The clinical manifestation, laboratory findings and histological findings of three persons admitted to the hospital for acute hepatitis taking aloe preparation for months, met diagnostic criteria of toxic hepatitis. Upon discontinuation of the oral aloe preparations, liver enzymes returned to normal level. So, Aloe should be considered as a causative agent in hepatotoxicity2. If Aloe Vera is not processed properly it turned out to be poisonous. Over dose of Aloe can cause intestinal cramps leading to ulcers or irritated bowels. The use of aloe may result in allergic reactions, cramps and kidney damage 3. Also, overdose can lead to colicky abdominal spasms and pain, as well as the formation of thin, watery stools. Aloe should not be used during pregnancy except under medical supervision after benefits and risks have been evaluated according to WHO guidelines. People who are on steroids, pills for irregular heartbeat, diuretics, digoxin should not use Aloe. Also, people with intestinal disorders, pregnant and nursing mothers and children below 12 years should not use Aloe. On May 9, 2002, the U.S. Food and Drug Administration issued a final rule banning the use of aloe and cascara sagrada as laxative ingredients in over-the-counter drug products. Rectal bleeding or failure to have a bowel movement within 24 hours after use of a laxative may indicate a serious condition. Chronic use may cause dependence and need for increased dosages, disturbances of water and electrolyte balance (hypokalaemia), and an atomic colon with impaired function. One should be aware about the species of aloe used, as the juice of the leaves of certain species is poisonous, for example Aloe venenosa is poisonous. TURMERIC Curcuma longa is the most important species for the food industry and has a wide distribution in India. Curcuma longa is a small perennial herb native to India bearing many rhizomes on its root system. Benefits Turmeric is known to possess antibacterial, anticancer and antifungal activities. It is well recognized as the best anti-oxidant, hypoglycaemic, colorant, antiseptic and wound healer. It is the spice that gives Indian curries their characteristic bright yellow-orange colour. Turmeric is antiinflammatory to the mucous membranes, which coat the throat, lungs, stomach and intestines. Regular use of turmeric can benefit from Colitis, Crohn's disease, diarrhoea, and post-giardia or post salmonella conditions. The itching and inflammation that accompanies haemorrhoids and anal fissures can be reduced by use of turmeric. The healing properties of turmeric have made it a most widely used ingredient in cosmetics and drugs. Turmeric can also benefit skin conditions including: eczema, psoriasis and acne as a potent detoxifier. Although, turmeric gives the energy of the Divine Mother and grants prosperity of health, and is effectual for purification as well as purifying the path of the subtle body, still some adverse effects are reported when it is consumed along with some prescription drugs. Risks Turmeric may increase the risk of bleeding or potentiate the effects of warfarin therapy4. Also, use of turmeric is contraindicated during pregnancy as it can cause uterine stimulation5. The active constituent of turmeric, curcumin is reported in some studies to produce a marked increase in serotonin and noradrenalin levels at 10 mg/kg dose in frontal cortex and hippocampus also increased the dopamine levels in frontal cortex and striatum parts of mice brain6. Curcumin was found to inhibit monoamine oxidaze activity in the mouse brain. These findings suggest that the antidepressant effects of curcumin may involve the central monoaminergic neurotransmitter systems6. Reports suggest that turmeric should be used with caution for gall bladder problems 7. FENNEL Fennel (Foeniculum vulgare) is a plant species in the genus Foeniculum. It is a member of the family Apiaceae (formerly the Umbelliferae). It is a hardy, perennial, umbelliferous herb, with yellow flowers and feathery leaves. Benefits It is a highly aromatic and flavourful herb with culinary and medicinal uses. Fennel may be an effective diuretic and a potential drug for treatment of hypertension 8-9. Fennel can be made into a syrup to treat babies with colic (formerly thought to be due to digestive upset), but long-term ingestion of fennel preparations in babies is a known cause of thelarche. Ancient Romans regarded fennel as the herb of sight. Root extracts were often used in tonics to clear cloudy eyes. Extracts of fennel seed have been shown in animal studies to have a potential use in the treatment of glaucoma. On account of its carminative properties, fennel is used medicinally with purgatives to allay their side effects, and is also one of the main ingredients of the wellknown compound liquorice powder. Fennel can act as a diuretic and a natriuretic 9. The results of study conducted on genital organs of male and female rat had confirmed the oestrogenic activity of the fennel seed extract10. Fennel has been reported to increase milk secretion, promote menstruation11. Risks Fennel is found to show some allergic reaction12. Occupational rhinitis and asthma in an atopic individual is reported which mainly involved sensitivity to unique allergens present in fennel 13. EUCALYPTUS Eucalyptus belongs to family Myrtaceae and it is used as Stimulant, antiseptic and aromatic. There are a large number of species of Eucalyptus trees yielding essential oils, the foliage of some being more odorous than that of others, and the oils from the various species differing widely in character. About twenty-five species are at the present being utilized for extracting oil. The British Pharmacopoeia describes Eucalyptus Oil as the oil distilled from the fresh leaves of Eucalyptus globulus and other species. Benefits Eucalyptus Oil is used as a stimulant and antiseptic gargle. It impairs sensibility of skin on local application, and known to increase cardiac action. An emulsion made by shaking equal parts of the oil and powdered gum- Arabic with water has been used as a urethral injection, and has also been given internally in drachms doses in pulmonary tuberculosis and other microbial diseases of the lungs and bronchitis. In croup and spasmodic throat troubles, the oil may be freely applied externally. The oil is an ingredient of 'catheder oil,' used for sterilizing and lubricating urethral catheters. Risks But Eucalyptus oil is reported to cause dermatological side-effects, which deserves further systematic investigation, as eucalyptus oil is used widely in dermatological preparations14. Eucalyptus can cause depression of conscious state, drowsiness, unconsciousness, vomiting or ataxia. Ingestion of eucalyptus oil caused significant morbidity in infants and young children. So it should not be recommended for children 15. Accidental ingestion of eucalyptus oil by a three year old boy caused profound central nervous system depression within thirty minutes, but he recovered rapidly after gastric lavage. The extreme toxicity of eucalyptus oil is emphasised in literature16. Survey of the literature showed that essential oils of eleven plants are powerful convulsants due to their content of highly reactive chemical constituents, and eucalyptus is one of them. Three cases strongly support the concept of plant-related toxic seizure17-18. Eucalyptus oil is well documented as being extremely toxic if ingested. The statement is supported by a case of systemic eucalyptus oil toxicity on topical application. A six year old girl presented with slurred speech, ataxia and muscle weakness and progressing to unconsciousness following the widespread application of a home remedy for urticaria containing eucalyptus oil14. Contact allergies to eucalyptus oil have also been reported 19. CLOVE Clove is the dried flower bud of Eugenia caryophyllus belonging to family Myrtaceae. Clove oil is 60 to 90% eugenol. Benefits Cloves fights germs, viruses and bacteria, and it encourages the loosening of phlegm from the respiratory system. It also promotes sweating with fevers, colds, and flu, which is very healing. It is often used in herbal remedies for whooping cough. Clove oil is the active ingredient of several mouthwashes and a number of over-thecounter toothache pain-relief preparations. Clove is also reported to relax the smooth muscle lining of the digestive tract. A few drops of the oil in water will stop vomiting, and clove tea will relieve from diarrhoea, gas, bloating, intestinal spasms and nausea. Dentists use clove oil as an oral anaesthetic. They also use it to disinfect root canals. Clove oil has been used to stop pain of toothache when dropped into cavity. Clove essential oil is the powerful antioxidant.