What is the test for deliberate indifference to a serious medical need?

For a prison official to act with deliberate indifference to a serious medical need, the prison official must knowingly disregard an excessive risk to a prisoner's health. Peralta v. Dillard, 744 F.3d 1076, 1082 (9th Cir. 2014) (en banc). This requires the prisoner to show "that the course of treatment the [prison official] chose was medically unacceptable under the circumstances and that the [prison official] chose this course in conscious disregard of an excessive risk to the [prisoner's] health." Hamby v. Hammond, 821 F.3d 1085, 1092 (9th Cir. 2016) (citation and internal quotation marks omitted).