**4.2. Garlic**

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

#### **4.3. Ginkgo**

Ginkgo (*Ginkgo biloba*) and its leaf extracts contain active compounds which have been found to improve circulation and cognition. The extracts are sold in both solid and liquid forms and appear to be relatively safe [28]. Medicinal use of ginkgo dates back 2800 BC, the seeds are used as an expectorant, antitussive and anti-asthmatic, and the leaves aid in asthma and cardiovascular disorders [26]. The most common side effects are dizziness, headache, restlessness, vomiting, nausea, diarrhea and dermal sensitivity. Cross-allergenicity with poison ivy has been reported. Ginkgo as an inhibitor of platelet-activating factor may alter bleeding times, therefore it may cause an upsurge of the anticoagulant effect of aspirin and warfarin [28].

**4.7. Ma huang**

**4.8. Valerian**

and hands [28].

**5. Why people use herbal medicine?**

rely on herbal medicine for their basic healthcare needs [36].

**5.2. An alternative approach to healthcare**

**5.1. Accessibility and affordability**

Ma huang (*Ephedra sinica*) is a medicinal plant traditionally used to treat hay fever, bronchial asthma, colds, coughs, enuresis, myasthenia gravis, narcolepsy, rheumatism and chronic postural hypotension. It contains a number of alkaloids including ephedrine and pseudoephedrine [26]. Ma huang is not considered as a safe herb, with adverse effects including insomnia, dizziness, headaches, nervousness, stroke, seizures, hypertension, psychosis, irritability, myo-

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Valerian (*Valeriana officinalis*) is a medicinal plant commonly used as a mild sedative and anxiolytic. Numerous constituents are found in the root of this plant, valerenic acid (C15 sesquiterpenoid) and valerena-4,7(11)-diene have been suggested to possess the active ingredients accountable for the sedative effect [30]. Valerian has been reported to cause excitability, headache, gastrointestinal complaints and ataxia. An oral overdose may result in abdominal cramps, onset of fatigue, light headedness, chest tightness, and tremors of feet

The documentation of medicinal plants of numerous cultures is extensive, these plants have been used in treating various diseases even without the knowledge of their constituents and accurate functions [31]. The high practice of herbal medicine is due to cultural acceptability, as plant remedies have been around for centuries [32]. In countries such as Zambia, Tanzania and Uganda the ratio of herbal medicine practitioners to the population was found to be 1:200–1:400. However, the ratio of western medicine practitioners is 1:20,000 or less [33]. A survey conducted in 1991 revealed that traditional practitioners in sub-Saharan Africa out number western practitioners by 100 to 1 [34]. Herbal medicine has remained affordable in comparison to high cost western medicine [35]. In over populated countries such as India, the rural population has almost no access to modern medicine, therefore, they are compelled to

Plants are perceived to be healthier than conventional biosynthetic drugs. Reports on conventional drugs adverse effects has been found to be much higher compared to herbal toxicity reports [4]. Other reasons for the use of herbal medicine include: (i) several claims on the efficacy and safety of plant medicines [11], (ii) improvements in the quality of herbal medicines with the development of scientific evaluation [21], (iii) to relieve symptoms related to chronic or

cardial infarction, premature ventricular contraction and death [28].

#### **4.4. Ginseng**

Ginseng (*Eleutherococcus senticosus*) is the fourth most extensively used Chinese medicinal herb, treating a variety of conditions. It is used as a general tonic and is claimed to increase the body's resistance against stress and builds up general vitality besides treating diabetes, depression and hypertension [29]. Products are made from dehydrated roots, such as extracts, elixirs and tea, also tablets and capsules. Numerous active constituents, ginsenosides, respectively have specific pharmacologic effects that sometimes compete with each other, thus the whole root is used in preparations [28]. Excessive doses of ginseng have been reported to cause insomnia, agitation and elevation of blood pressure, mastalgia and vaginal bleeding have been detected at acclaimed doses [8].

#### **4.5. Kava**

Kava (*Piper methysticum*) is believed to be beneficial for health by soothing nervous illnesses, inducing sleep and relaxation, reducing weight and counteracting fatigue. It is often used to treat asthma, urinary infections, fever, headaches, syphilis, rheumatism and gonorrhea, it is also used as a stomachic and diuretic [26]. Kava is commonly known as an anxiolytic agent. Reported side effects include dizziness, gastrointestinal discomfort, headaches and localized numbness after oral ingestion. Long term use at high doses may cause scaly, dry skin and discoloration of nails and the skin, eye redness and photosensitivity. Diplopia and photophobia may also occur after excessive consumption. Interaction of central nervous system depressants and kava may lead to a comatose state [8, 28].

#### **4.6. St John's wort**

St John's wort (*Hypericum perforation*) is specified to possess astringent and sedative properties. It has been used for neuralgia, excitability, fibrositis, menopausal neurosis, sciatica, wounds, depression and anxiety. Modern interest is focused on its antidepressant use [26]. St John's wort possesses active compounds such as hyperforin, hypericin and melatonin. It is reported to have side effects which include fatigue, constipation, nausea, vomiting, dry mouth, headaches, dizziness and photosensitivity [8].
