truth serum vs truth drug

truth serum and truth drug both are nouns.

Word	Noun	Adjective	Verb	Adverb
truth serum	Yes	No	No	No
truth drug	Yes	No	No	No

As nouns, truth serum and truth drug are synonyms defined as:

truth serum and truth drug: an intravenous anesthetic drug that has a hypnotic effect; induces relaxation and weakens inhibitions; is believed to induce people to talk freely

truth serum (noun)	truth drug (noun)
an intravenous anesthetic drug that has a hypnotic effect; induces relaxation and weakens inhibitions; is believed to induce people to talk freely	an intravenous anesthetic drug that has a hypnotic effect; induces relaxation and weakens inhibitions; is believed to induce people to talk freely