Lance Stephenson scored 20 points and West finished with 17 for the Pacers, who lost their third in a row, matching a season high.
The Nuggets got 10 points from Timofey Mozgov, who moved up in the rotation to play significant minutes in place of injured JaVale McGee. The 7-foot McGee was sidelined by soreness in his left shin. He was scheduled to undergo an MRI on Tuesday to try to determine the severity of the injury.
Denver also was without another top reserve, Wilson Chandler, a late scratch because of a left groin strain.
After Stephenson made a layup to pull the Pacers within a point with 5:47 remaining in the third, the Nuggets scored 10 of the next 13 points en route to taking an 82-74 lead into the fourth quarter. Gallinari got the run going by converting a three-point play and sinking a 3-pointer the next time down the floor.
Lawson's layup capped a 6-0 run and put the Nuggets up 96-82 with 6:44 remaining.
Roy Hibbert started a tying 13-0 run for the Pacers as he broke free underneath for a dunk and George had a four-point play to pull the Pacers to 99-97 with 3:08 remaining.
Iguodala went to the line twice in the next minute but missed four throws and Hill put in a floater from 10-feet away to even the score with 1:58 left.
Gallinari made two free throws with 59.7 seconds left before West answered with a putback to re-tie the score at 101 with 38.6 seconds remaining.
NOTES: The Nuggets did not make a field goal in the final 5:45. ... The Pacers re-signed F Sam Young, bringing him back to the team three weeks after releasing him. ... The Pacers have lost seven of their last eight games in Denver. ... Gallinari has led the Nuggets in scoring 14 times this season with the Nuggets going 11-3 in those games. ... Mozgov's 10 points represented a season-high. ... The Pacers have allowed at least 100 points in three consecutive games, a season high.