He completed his secondary studies at the Padres Franceses in Santiago, and later graduated as a medical doctor from the Universidad de Chile in 1921.

Between 1937 and 1938 Cruz-Coke served as Minister of Public Health, Social Assistance and Welfare appointed by President Arturo Alessandri.

He set up a "National Food Council" (Spanish: Consejo Nacional de Alimentación) that defined innovative policies to improve the alimentary weaknesses, particularly among the low-income sectors, and organized the Preventive Medicine Services to diminish labour sickness.

In 1946, he was proclaimed presidential candidate by the Conservative party, but a split of his voting base between him and Fernando Alessandri resulted in the triumph of Gabriel González Videla, with Cruz-Coke finishing in second place.

In 1963 he was named the first president of the newly established National Committee on Atomic Energy (Spanish: Comisión Nacional de Energía Atómica), and in 1965 produced the first plan for the use of nuclear power in the mining industries of the north of Chile.