Medicinal plants of Otwal and Ngai Sub Counties in Oyam District, Northern Uganda

World wide over 80% of the people depend on medicinal plant species to meet their day today healthcare needs [1]. Rural household of Uganda rely heavily on plant resources for food, fodder and herbal medicine [2]. Tabuti [2] further asserted that savanna environment contains many plant resources of economic values such as foods and medicines. These resources are widely relied on by rural communities in developing countries because of inefficiencies in service delivery or because social services and goods are unaffordable. For this reason many people are currently resorting to traditional medicine for primary health care due to high costs in accessibility, cultural compatibility, self-reliance among others [3]. They also employ herbal medicines because of cultural preferences and perceived effectiveness [4, 5].

Medicinal plant species form a main part of treatment for the rural poor. Traditional medicine usage in rural Ugandan population for day-to-day health care needs is close to 90% [6]. Kamatenesi and Oryem [6] further reported that women and children form the bulk of the people reliant on herbal medicine. According to Katuura et al [7], malaria was reported to be the most common condition treated by traditional healers in Mbarara District. The use of traditional herbal remedies is encountered in both rural and urban areas in Mali and that traditional medicine is one of the surest means to achieve total health care coverage for African's population [8].

Discourses on the future of traditional medicine in Africa and other indigenous societies often assume government recognition and integration into the formal health care systems [9].

In certain areas in Nigeria, the only health care providers close to the people are the traditional medical practitioners [10]. However, it should be noted that medicinal plant species have also been discovered to have other uses as some could be used as vegetables, fruits, trees and ornamentals [11].

Health services in Oyam District are inadequate, and only 15 out of the 43 parishes in Oyam District have health facilities. Maternal mortality rate is still high because clean and safe deliveries are at only 14% because it is mainly the traditional birth attendants (TBA) who play a significant role [12].

A total of 110 respondents were interviewed from the study area; 46 were females and males were 64 as shown in table 1.

From the research findings, 71 medicinal plant species both wild and cultivated belonging to 42 families were documented and identified in the study area (Table 2). The family Asteraceae (5 species) was the most represented followed by Leguminosae and Lamiaceae (4 species) plant species each; Solanaceae, Poaceae, Eurphorbiaceae, and Zingiberaceae had 3 plant species in each family, and the remaining families had two and one species. With regard to growth habits, the plant species consisted of shrubs (39%), herbs and climbers (36.6%), trees (21%) and grasses (4%).

These plant species were mainly obtained from open grassland area (41%), garden or farms (21%), homestead (13%) wooded grassland 11%, forest (7%) and least number was obtained from swamps (4%) and forest edge (3%).

The most commonly mentioned plant species by respondents were Clerodendrum umbellatum Poir (25%) Securidaca longipedunculata Fres. (17%) while the least mentioned among respondents includes; Crotalaria ochroleuca G.Don, Albizia coriaria Welw (0.9%). Fifty five percent of the plant species mentioned were used to treat more than one disease and 45% to treat only one disease.

A total of plant species documented, 25% were edible and formed part of local diet (Table 2). Fifty five percent of these were used in the treatment of more than one disease while 45% were believed to treat only one particular disease. The conservation status of the medicinal plant species is such that only 10% were cultivated and 90% were collected from the wild (Table 2).

Roots were the commonest plant parts (57%) being used; followed by leaves (23%) (Figure 2). The most underutilized plant part were found to be flowers with only 2% usage, fruits making up 3% and the rest of plant parts harvested making up 4%, 5% and 7% of stems, seeds and bark respectively.

Records reveal that a total of 41 conditions were treated with medicinal plant parts in Otwal and Ngai sub-counties in Oyam District. The common condition being treated in Ngai and Otwal sub counties was found to be abdominal pains and this was reported by 11% of the respondents, followed by cough at 10%. Other conditions such as wounds had 5.6% headache; epilepsy and STD/STI at 4.6%. Those least mentioned at below 1% were impotence, toothache, cholera, fever among others.

The most common way of preparing these medicinal plant species was mainly by crushing and extracting using cold water making up an overall 48%. This was followed by crushing plant parts and applied in that form at 20%. The least mode was found to be burning, and adding the ashes into bath water making up less that 1%.

On administration, oral administration through drinking was found to be the most frequently used at 69% and the least were through bathing with, massaging and smoking at less than 1%.

The main sources of indigenous knowledge of medicinal plant species were parents at 40%, grandparents at 35% (Table 3). The least sources of information about medicinal plant species were through dreams at 3.8% and in-laws 2.9%.

The use of medicinal plant species was found to be driven mainly by its perceived effectiveness (34%), poverty, medical facilities being far (23%) and lack of medicines in hospitals (5%) (Table 4). The least use of medicinal plant species was due to referral from medical personnel (3%).

The 71 medicinal plant species of cultivated and wild types were greatly utilized by people of Oyam District as herbal remedies. These plant species fall under 42 families, with the family Asteraceae having the highest number of medicinal plant species. The family Asteraceae was also recorded as having the most number of medicinal plant species as other studies in other areas also reveals [15, 16]. Clerodendrum umbellatum, Securidaca longipedunculata, Clematis hirsuta and Conyza sumaternsis were among the most frequently utilized species. The frequency of mention of a given plant species could be an indication of the prevalence of a given condition it can treat and its therapeutic values.

Roots were the most commonly harvested plant part of the medicinal plants compared to any other part. This form of harvesting however, is threatening to the survival of the plant. Plant species such as Lantana camara, Urtica massaica had leaves and roots being harvested. Harvesting of two or more plant parts can be more damaging especially when the roots and barks/stem are harvested. Thus from the conservation point of view, the high utilization of roots of plant species in Oyam District put these plant species at a risk because of the damages inflicted on the plant species. This was also noted in other areas [6].

Many of these plant species treated more than one condition and are being used in combination. This pattern of using medicinal plant species for varying conditions was also observed among the local communities in Mabira Forest Reserve area [15]. However, it was found that locals usually mix the medicinal plant species to ensure effectiveness in treating a given ailment [17, 18]. This was also observed in Ngai Sub County, where the extent of knowledge of medicinal plant mixing determined the success of a traditional healer. Medicinal plant are strongly believed by the local people of Ngai and Otwal to be effective and this among other reasons explain why they have continued to use them, thus their reliance on them for basic healthcare. This trend was also observed among the people living around Queen Elizabeth National Park in western Uganda [3, 6]

The most common method of preparation of medicinal plant species before being administered was found to be applied to most plant species. This involved crushing and extracting plant materials using cold/warm water and boiling. Those that were boiled were effectively extracted compared to use of cold water, since boiling also preserves the medicine longer. Oral administration was noted as number one mode of dispensing of herbal medicine. This mode of administration of herbal medicine was also reported elsewhere [6, 18].

Some of these plant species are popular and used all over Uganda and are on sale in most markets. For instance Cleome gynandra, Cajanus cajan, Vitallaria paradoxum, Capsicum frutescens were found to be sources of food and were being eaten not only locally but also nationally and internationally [3].

Some studies carried out in and outside Uganda showed that some of these plant species were potent as medicine. A plant like Aspilia africana, is said to have high antiplasmodial activity [19]. Some other plant species mentioned elsewhere as medicine include Cassia occidentalis which is used in Burkina Faso as stimulant [3].

Roots were the most commonly harvested plant part of the medicinal plant species compared to any other part. The most common method of preparation of medicinal plant species before being administered was found to be applied to most plant species. However, it was noted that some of these medicinal plant species are disappearing very first. The disappearance of medicinal plant species can be attributed to over use, agricultural activities and insecurity. Domestication of medicinal plant species is probably not taken seriously.

The use of medicinal plant species in primary health care is still a common practice in Ngai and Otwal Sub-County. The inadequate health services and abject poverty still make these people dependent on herbal medicine for their day to day health needs.

The generation gap caused by the over 20 years of insurgency in the area has brought about knowledge gap between the young and the old with regard to medicinal plant species.