camphor injection (historical cardiotonic)
Historical medical term; a camphor-based injection used as a heart stimulant in Japan until the late 1950s. Now primarily encountered in historical or medical contexts.
Until the 1950s, camphor injections were used as a cardiotonic.
shot in the arm; stimulus; impetus
Figurative use derived from the historical medical injection; refers to something that provides a sudden boost, encouragement, or revitalization, often in economic, organizational, or motivational contexts.
The new investment was a shot in the arm for the local economy.
His words of encouragement gave the team a shot in the arm.