drastic
adj.adj. describing a change or action that is very strong, sudden, and often extreme. You use it when a small change is not enough to solve a problem.
adj. characterised by extreme, rapid, or radical measures. Often describes a significant departure from a previous state or a severe response to a crisis.
The company had to make drastic changes to save money.
The doctor warned that if the medication didn't work, more drastic measures like surgery would be necessary.
The sudden collapse of the market forced the government to take drastic action, implementing emergency regulations that would have been unthinkable only a week prior.
From Ancient Greek δραστικός (drastikós, “active, efficient”), from δρᾶσις (drâsis, “strength, efficacy”), itself from δράω (dráō, “to do”).
Commonly modifies nouns like 'measures', 'changes', 'action', or 'cuts'.