Health & Medicine in the 9th century

11 sourced entries, 805 CE to 890 CE, oldest first. Also see Health & Medicine across every century or everything else in the 9th century.

• 805August 31 – Shunzong issues an edict to yield the throne to his son Xianzong (Li Chun), because of an illness, taking for himself the title of "Retired Emperor" (Taishang Huang). Xian is confronted with political disputes in Zi Prefecture (Shaanxi).source
• 822February 6 – Ukit Took becomes the last ruler (ajaw) of the Mayan city-state Copán (modern Guatemala). After his death in 830, the kingdom is wiped out, most likely from an epidemic.source
• 830Byzantine–Arab War: Muslim reinforcements from Ifriqiya and Al-Andalus (modern Spain) defeat Byzantine forces under Theodotus in Sicily, but a plague once again compels them to retreat to Mazara del Vallo, and evacuate to North Africa.source
• 830The Ad-dimnah Hospital (bimaristan) is created in Kairouan (modern Tunisia), by the Aghlabid emir Ziyadat Allah I.source
• 843Theodora II orders a persecution against the Paulicians throughout Anatolia; about 100,000 followers in the Byzantine theme of Armenia are massacred.source
• 857The first recorded major outbreak of ergotism kills thousands of people in the Rhine Valley. They have eaten bread made from rye infected with the ergot fungus parasite Claviceps purpurea (approximate date).source
• 869The first Gion Festival is held in order to combat an epidemic thought to be caused by an angry deity.source
• 872In Egypt, the first hospital (bimaristan) is built in Cairo by the Abbasid governor, Ahmad ibn Tulun. Physician licensure becomes mandatory in the Abbasid Caliphate.source
• 883Guy II of Spoleto begins a revolt, and assembles an army supported with Arab auxiliaries. King Charles the Fat sends Berengar of Friuli with an expeditionary force to deprive him of Spoleto. An epidemic ravages Berengar's army, and forces them to retire.source
• 888Lord Æthelred II of the Mercians is struck down with a debilitating illness. His wife, Princess Æthelflæd (a daughter of Alfred the Great) of Wessex, joins him as joint ruler of Mercia (approximate date).source
• 890King Donald II of Scotland expels the British aristocracy of Strathclyde. They flee south to North Wales.source