With the postseason all but in hand, Lowell wanted to get the treatment now to make sure he is as healthy as can be for the postseason, which is likely to start for the Red Sox in Anaheim on Oct. 8.
Lowell likely won't play in this three-game series against the Blue Jays.
In late June, Lowell had a shot of Synvisc, which is a lubricant that coats the joint. This was the first time this season he's had cortisone.
"More Synvisc, with a cortisone chaser," said Lowell. "We were talking about it a couple of weeks ago. Just to, more of heading into the postseason, I'd rather be with more mobility than less. I spoke to the doctors, and they said this would be a way to alleviate the pain, and it's looking pretty good. This was a good time to take two or three days off to really get my hip, hopefully, feeling a lot better."
Following his last shot, Lowell, once he was activated following the All-Star break, caught fire at the plate, hitting .389 over the next 10 games. He followed by hitting .319 with five homers and 15 RBIs in August.
The veteran has dipped a little in September, hitting .234 with one homer and 10 RBIs in 64 at-bats. For the season, Lowell is hitting .290 with 17 homers and 75 RBIs over 438 at-bats.
"He doesn't complain much," said Red Sox manager Terry Francona. "I can't imagine that he feels like he's 18 years old anymore. He does a really good job. Anybody that's been around him knows that he plays. What we watched last year until he couldn't play is a testament to that. This is just something -- this is the last chance to do something like this. Again, I guess we're trying to keep our house in order is the best way to put it."
The effectiveness of the last shot gave Lowell confidence that this one will help him have a strong finish during the most important time of year.
"They took out a decent amount of fluid again and I feel that instant relief, but I feel the soreness of the needle being inside," said Lowell. "I think after a couple of days I think it will feel really good. I don't think this was a necessity, but why not do something that's not going to hurt me and will make me feel better?"
With Lowell out of the lineup on Monday, the Red Sox played Casey Kotchman at first base while Kevin Youkilis moved across the diamond to play third.
Ian Browne is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.