Ethnopharmacological relevance: In this study, we compare the traditional medicinal knowledge and associated spiritual practices of healers with that of non-healers, to understand the relevance of healers in contemporary times. Given that Brunei Darussalam is well-known for its forest cover, the study also aims to understand the number of species collected from the forests, compared to those from human influenced habitats. Materials and methods: A total of six specialist healers from Belait, Tutong, Dusun and Iban communities, and seven non-healers who had personal experience in self-medication using medicinal plants participated in the study. We identified the specialist healers through purposive sampling, on the basis of their reputation in the locality, while the non-healers were those experienced in self-medication, recommended by the healers. Informants were interviewed at their residences, followed by collection trips to the plant habitats. We classified the total recorded ailments into 15 disease categories. We then compared the medicinal uses cited by healers to those mentioned by non-healers, as well as with prior published records from Brunei Darussalam. We also compare the habitats of species cited by both healers and non-healers to understand the dependency of the local pharmacopoeia on forests and human-influenced habitats. Results: Our study records 175 medicinal plants belonging to 85 families, the majority of which (92) were exotic to Borneo. There were 110 species collected from disturbed, human influenced habitats such as roadsides, agricultural fields, secondary and degraded forests, and homestead lands, while 58 species were collected from the forests surrounding Kiudang. Majority of the plants used by both healers and non-healers were collected from human-influenced habitats, indicating that the local pharmacopoeia could be a disturbance one. Most of the medicinal plants recorded in this study were used to treat chronic, but non-life threatening conditions. Ailments affecting the digestive system were the most targeted group with 67 species used. All medicinal uses with more than one citation were recorded from healers. Medicinal uses cited by healers also had greater correspondence with prior published reports from Brunei Darussalam. Healers believe that combining medicinal plants can produce a synergistic effect. Our study found that traditional knowledge related to healing practices is mostly transmitted vertically from parents to children. We also show that a ritual gift (pikaras) and invocations characteristic of the beliefs of the healers play an important role in facilitating healing. Conclusion: Our study adds further evidence to prior studies that the medicinal plants and healing practices in the Kiudang region could be considered as disturbance pharmacopoeia. Healers with their knowledge on both therapeutic and spiritual aspects of healing continue to play an important role in local healthcare.