drug, dragged
drug pertains to a medicinal substance, not a pulling action
dragged is the past tense of drag (I dragged myself out of bed.)

due to, because of
due to modifies nouns (The game postponment was due to rain.)
because of modifies verbs (The game was postponed because of rain.)

elicit, illicit
elicit means to bring forth (I tried to elicit a response.)
illicit means illegal (The drugs were illicit.)