what medication do they use?
Ayurveda and use Buddhist Chantings (Pirith).
Sinhalese people
Traditional Sinhalese villages in early days had at least one chief Medical personnel called Weda Mahaththaya (Doctor). These people practice their clinical activities by inheritance. Sinhalese Medicine resembles some of Ayurvedic practices in contrast for some treatments they use Buddhist Chantings (Pirith) in order to strengthen the effectiveness.

According to the Mahavamsa, the ancient chronicle, Pandukabhaya of Sri Lanka (437 BC-367 BC) had lying-in-homes and Ayurvedic hospitals (Sivikasotthi-Sala) built in various parts of the country. This is the earliest documentary evidence we have of institutions specifically dedicated to the care of the sick anywhere in the world. Mihintale Hospital is the oldest in the world.
who was the first to composed law books in sri lanka The Anuradhapura Kingdom. what is this kingdom? It was the first established kingdom in ancient Sri Lanka and Sinhalese people. what does these aforesaid people belong? Sri Lanka. what culture do they follow? Its main domains are sculpture, fine arts, literature, dancing, poetry and a wide variety of folk beliefs and rituals traditionally.
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Sinhalese people [SEP] Medicine
Traditional Sinhalese villages in early days had at least one chief Medical personnel called Weda Mahaththaya (Doctor). These people practice their clinical activities by inheritance. Sinhalese Medicine resembles some of Ayurvedic practices in contrast for some treatments they use Buddhist Chantings (Pirith) in order to strengthen the effectiveness. According to the Mahavamsa, the ancient chronicle, Pandukabhaya of Sri Lanka (437 BC-367 BC) had lying-in-homes and Ayurvedic hospitals (Sivikasotthi-Sala) built in various parts of the country. This is the earliest documentary evidence we have of institutions specifically dedicated to the care of the sick anywhere in the world. Mihintale Hospital is the oldest in the world.