What does "shock therapy" mean?

The use of a single, very large dose of a medicine.

Shock therapy

Common synonyms include: actinotherapy, aerosol therapy, aerotherapeutics, aerotherapy, arsenotherapy, autoserum therapy.

noun, slang

noun, slang ·Moderate ·High school level

Noun

1
The use of a single, very large dose of a medicine. uncountable, usually
2
treatment of certain psychotic states by the administration of shocks that are followed by convulsions wordnet
3
A government policy of a sudden release of price controls and immediate trade liberalization within a country. informal, uncountable, usually
4
Synonym of electroconvulsive therapy. uncountable, usually

From shock + therapy. The medical sense first appears c. 1917 in the Journal of Experimental Medicine.