Traditional Batak medicine

In traditional Batak society datuk (animist priests) as well as gurus practiced traditional medicine, although the former were exclusively male. Both professions were attributed with supernatural powers and the ability to predict the future. Treatments and healing rituals bear some resemblance to those practiced by dukuns in other parts of Indonesia. Following the Christianization of the Toba and Karo Batak in the late 19th century, missionaries discouraged traditional healing and divination and they became largely clandestine activities.^[35]
Both datuk and guru healers also practiced divination by consulting a pustaha, a handwritten book made of wood and bark in which were inscribed recipes for healing remedies, incantations and songs, predictive calendars, and other notes on magic, healing and divination written in poda, an archaic Batak shorthand. According to Winkler, there were three categories of Pustaha based on the purpose of their usage:

1. Protective Magic, which includes diagnosis, therapy, medicinal mixes which have magical properties, such as amulets, parmanisan (love charms), etc.

2. Destructive Magic, which encompasses the art of making poison, the art of controlling or utilizing the power of certain spirits, calling the pangulubalang, and the art of making dorma (magical formulas for causing a person to fall in love).

3. Divination, which involves oracles (words of the gods), the wishes of the spirits, commands from the gods and from the spirits of the ancestors, and an almanac or calendrical system (porhalaan), and astrology to determine auspicious days and months to accomplish certain actions or goals.^[37]

The datu or guru consulted the pustaha when presented with a difficult problem, and in time this became in itself a ritual. When missionaries began to discourage traditional healing and augury the Bible may have been adopted by some gurus in place of the pustaha.
Among the most important healing ceremonies performed in Toba and Karo communities is that of recalling the jinujung, or personal guardian spirit. According to Toba and Karo cosmology, each person receives a jinujung in childhood or at puberty and they keep it for life unless they are unfortunate enough to lose it, in which case they will fall ill. In order to call the jinujung back, a female guru (guru sibaso in Karo) goes into a trance and the jinujung will enter into her and speak through her mouth. At this time the sick person or the family can negotiate ritual payment to entice it to return.^[38]
Traditional healers are not powerful enough to cure illness due to the loss of a person's tendi (this falls under the jurisdiction of the datuk), however they do play a role in communicating with begu and influencing their behavior.