**1. Introduction**

The practice of herbal medicine is the oldest form of healthcare which has been used for decades in developing and developed countries. Primitive people have depended on nature for food, shelter, clothing and medicine to cure ailments. These humans distinguished useful herbs with beneficial effects from those that were inactive or toxic [1]. According to literature approximately 50,000 plant species are stated to have medicinal properties [2]. Thus, the basis of modern medicinal drugs such as aspirin, morphine, digitoxin and quinine were synthesized through scientific validation of herbal medicine [3, 4]. Plant based drugs awareness advanced gradually and has been passed on, therefore setting a foundation for many traditional medicine systems around the globe [1].

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Today herbal medicine is still the primary healthcare system for about 80% of the world's population, especially in the developing countries [1, 5, 6]. There has been also a sudden increase in the utilization of herbs as prescription drugs in developed countries such as France and Germany [3, 7]. However, there is a concern that not all herbal medicines are safe as reported [8]. Over the years the use of traditional medicine has provided us with valuable formulas on the selection, preparation and application of herbal remedies. The same vigorous method clinically and scientifically must be implemented to verify the effectiveness and safety of curative products, to be viable alternative to western medicine [4].

**3. Historical perspective of herbal medicine**

1500 years with approximately 148 formulations [25].

cause morbid spontaneous spinal epidural hematoma [8, 28].

**4. Common herbal medicines**

**4.1.** *Echinacea purpurea*

**4.2. Garlic**

The use of plants as medicines dates 60,000 years ago according to ancient Babylon reports. In Egypt and China written material on herbal medicine dates approximately 5000 years back, in Asia Minor and Greece it dates 2500 years ago [21]. There are various herbal medicinal systems, the practices and philosophy of each are influenced by the region within which it first evolved [22]. In China, they have their own system known as the Traditional Chinese medicine which has been used throughout history [23]. The oldest known herbal book in the world *The Devine Farmer's Classic of Herbalism* was compiled in China about 2000 years ago, numerous herbal pharmacopeias and various monographs on specific herbs exist through the composed information on herbs [3]. Ayurveda, a healthcare system that has been used in India for over 5000 years, that was founded by ancient Hindu healers and saints. Its *materia medica* provides a comprehensive description of over 1500 herbs and 10,000 formulations. The Indian government has recognized Ayurveda to be a complete healthcare system in comparison to western medicine [24]. Kampo medicine, the Japanese herbal medicine dates back over

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*Echinacea* has an extensive history on the use as medicines, mainly for infections such as septic wounds and syphilis, also as an anti-toxin for snakebites [26]. The species *Echinacea purpurea* from this genus is a well-known medicinal plant used in treating snake bites, toothache, skin disorders, bowel pain, chronic arthritis, seizure and cancer, traditionally [27]. *E. purpurea* possesses secondary metabolites including caffeic acid derivatives, alkamides, glycoproteins and polysaccharides alleged to be biologically and pharmacologically active [26, 27]. Allergic reactions can occur and are usually mild, but individuals with a history of asthma, atopy, or allergic rhinitis may experience severe allergic reactions that include dyspnea and anaphylaxis [26, 28]. Other adverse effects include abdominal pain, urticarial, nausea, erythematous, rash and pruritus [26].

Traditionally, garlic (*Allium sativum*) has been used to treat colds, chronic bronchitis, coughs, respiratory catarrh, bronchitic asthma and influenza [26]. Additionally it is used mainly to manage hypertension and hypercholesterolemia. It contains alliin, which upon chopping or crushing is activated by alliinase in the absence of acid or heat [8, 28]. Allicin produces both hydrophilic (cysteine) and lipophilic (sulfides, ajoene) sulfur compounds which are accountable for pharmacologic effects. Garlic is administered via oil-filled capsules, condensed dried powder, and enteric-coated tablets and capsules; it is also aged in aqueous alcohol [28]. Adverse effects of garlic extract include burning sensation in the gastrointestinal tract, diaphoresis, nausea, and light headedness. The extract may also cause contact dermatitis and excessive ingestion may
