|Traditional Medicinal Plants (Dar Es Salaam University Press - Ministry of Health - Tanzania, 1991, 391 p.)|
|PART I: USE AND PROMOTION OF TRADITIONAL MEDICINAL PLANTS IN THE AFRICAN REGION|
ALUOCH, J.A., KOFI-TSEKPO, W.M.
WAKORI, E.W.T., RUKANGA, G.M. and TOLO F.
Kenya Medical Research Institute
A traditional medicine for bronchial asthma was identified through interaction with a traditional healer, Mr. Charles Obuya of Rangwe, South Nyanza. The traditional medicine regimen consists of three different liquid preparations:
(1) A cold aqueous root-bark extract used for diagnosing the disease.
(2) An oral liquid medicine for regular treatment, prepared by boiling plant roots in water.
(3) An oral liquid medicine for regular treatment, prepared by boiling plant stem and leaves in raw ghee.
This traditional medicine regimen is said to produce curative effects in very few weeks. Basic ethnomedical information indicated a high potential in this medicine and this led us to take more interest in the investigation. Phytochemical screening of the drug plant materials, revealed the presence of flavonoids, terpenoids, alkaloids and glycosides. Preliminary animal toxicity studies indicate that the medicine is reasonably safe. There is abundant evidence that the medication has a promising therapeutic effect in man and a clinical study is being planned. The steps taken so tar in the development of this traditional medicine for bronchial asthma will be discussed.
Since traditional medicine has been shown to have intrinsic utility, it should be promoted and its potential developed for wider use and benefit to mankind (WHO, 1978). In view of this, the Traditional Medicines and Drugs Research Centre of the Kenya Medical Research Institute, has been able to establish some form of dialogue with the traditional healers on an interactive basis. This has enhanced research on traditional medicines to establish their efficacy and safety.
Asthma is a common and important disease, characterized by widespread bronchial obstruction that is reversible either spontaneously or with therapy. Its principal causes seem to be allergy, infectious, irritants and psychological reactions (Heiner, et al 1973). The large number of conventional medicines currently in use for the treatment of bronchial asthma, are only able to control the disease but do not provide a complete cure. It has therefore been found necessary to develop an asthma traditional medicine prepared by Mr. Charles Obuya, which appears to be of very high potential.
The steps taken so far in the development of this traditional medicine for bronchial asthma are discussed below.
The traditional medicine for bronchial asthma was identified through interaction with a medicineman, Mr. Charles Obuya during field research. Several visits were made to his clinic to observe the treatment procedures, and the patients treated with the medicine.
The preparation and formulation of the medicines were observed. The traditional medicine regimen consisting of three different liquid preparations was noted to be prepared from three different plant materials. A medicine for diagnosing the disease is prepared by extracting a root bark in cold water. The cold extract is then administered intranasally at a single dose of 5 ml into each nostril. This results in profuse mucous secretion from the lungs. An oral liquid medicine is prepared by boiling plant roots in water, and the extract is administered at a dose of 200 ml twice a day for two months. A second oral medicine is prepared by boiling plant stem and leaves in water and raw ghee. This is also administered at a dose of 200 ml twice a day for two months or more, according to the severity of the disease.
The medicinal plants used to prepare the medicines were collected, and correct botanical information was obtained with the assistance of the botanists at the herbarium of the National Museums, Nairobi.
The research activities in the Institute have created interest in over 100 asthma patients, who have sought assistance from the Institute in order to use this traditional medicine for asthma. Our laboratories, on the other hand took this opportunity to monitor the conditions of these patients and found that all have responded to this treatment regime. The high potential observed with this medication has led us to take more interest in the investigations .
Phytochemical investigations of the plant materials carried out using thin layer chromatography revealed the presence of flavonoids, terpenoids, alkaloids and glycosides.
Pharmacology and toxicology
Preliminary animal toxicity studies were carried out in mice, and the results obtained indicated that the medicine is reasonably safe.
Isolated tissue experiments carried out using guinea pig tracheal rings revealed some antagonistic effects of one of the asthma preparations on the contractions caused by PGF2X.
The therapeutic claims of this medicine were first evaluated by observing the patients under treatment by Mr. Charles Obuya. The medicineman was then invited to our laboratories to carry out a clinical demonstration under the supervision of two physicians among members of the research team. Long function tests were carried out on the patients before and during treatment with the traditional medicine. A reversal of bronchoconstriction was noted on administration of the traditional medicine (Aluoch et al, 1987), indicating a reasonable level of efficacy. Thus there is abundant evidence that this medication is good and a clinical study is being planned.
Discussion and conclusion
In the context of cultural evolution, traditional medicine has always developed and preserved its role of providing care in all communities (WHO, 1978). Thus even if the active principles have not yet been identified in the plants used in traditional medicine, historical evidence of the value of such plants could result in useful preparations provided they are safe (Farnsworth, et al. 1985). The evaluation of chronic toxicity based on the ethnomedical information obtained from the traditional healer and acute toxicity investigated using laboratory mice, suggested that this asthma medication is reasonably safe. The only side effect observed so far is diarrhoea obtained with the use of the oral preparation boiled in raw ghee and water, but this is eliminated by reducing the dose of this medicine.
There are several possible mechanisms which might account for the anti-asthma effect of this traditional medicine. The presence of terpenoids as revealed by the phytochemical screening, may suggest corticosteroid-like mechanisms, e.g., inhibition of histamine formation or storage and the direct smooth muscle effect of steroids. The pharmacological experiments carried out on guinea pig tracheal ring, seems to suggest a prostaglandin pathway as another possible mechanism of action. Further evaluations of these medicines are in progress.
We pay a special tribute to the medicineman, Mr. Charles Obuya for his interest in our collaboration.
Aluoch, J.A., Kofi-Tsekpo, W.M., Were, J.B.O., Oyuga, Wakori, E.K., Nganga, L.W. and Obuya, C.O., (1987). In: Kinoti, S.N., Waiyaki, P.G., Were, J.B.O. (eds) Proc. 8th Annual Med. Sci. Conf. Nairobi, Kenya, p. 344-349.
Farnsworth, N.R. Akerele, O., Bignel, A.S., Soejarto, D.D. and Guo, Z. (1985): Bull. WHO, 63(6): 965-981.
Heiner, D.D., Tashkin, D.P. and Whipp, B.J. (1973): Ann. Inter. Med. 78: 405-419.
WHO (1978): The promotion and development of traditional medicine. Technical Report Series 622, Geneva.