What is acting rapidly and violently; efficacious; powerful; -- opposed to bland; as, drastic purgatives. -- n. (Med.) A violent purgative. See Cathartic called?

drastic — Acting rapidly and violently; efficacious; powerful; -- opposed to bland; as, drastic purgatives. -- n. (Med.) A violent purgative. See Cathartic. (Webster's 1913.)

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