Hoodia is a genus of succulent plants in the family Apocynaceae that is widely used traditionally by the San people of southern Africa as an appetite suppressant, thirst quencher and medicinally as a cure for severe abdominal cramps, haemorrhoids, tuberculosis, indigestion, hypertension and diabetes.

Hoodia alstonii, synonymously known as Trichocaulon alstonii and Trichocaulon halenbergense, is a rare South African indigenous species that occurs in the Northern Cape Province which extends northwards into Namibia.