Drummond finished with 4-of-5 shooting from the field overall and 12-of-12 shooting from the line for the Rockets (13-8, 5-3 Mid-American Conference). Julius Brown added 16 points and three assists, Nathan Boothe had 13 points and Jonathan Williams 11.
Toledo took an early lead and held it throughout the first half to a 35-33 edge at the break.
Brown sank a trio of jumpers - including one from distance - within 1:43 to extend the Rockets' lead to 62-52 with 11 minutes remaining in the second half. Williams followed with back-to-back 3-pointers to put Toledo up 70-58 with 8:21 to play and Northern Illinois could not get closer than five after that.
Darrell Bowie had 18 points and four rebounds for the Huskies (8-11, 2-6).