Pitta experienced concussion symptoms against the Pittsburgh Steelers, but is probable on the injury report.
"He's done the baseline," Harbaugh said. "He's cleared."
Pitta went to the locker room for evaluation after being tackled by Steelers free safety Ryan Clark and linebacker Lawrence Timmons following a short catch during the Ravens' 13-10 win last Sunday night and didn't return.
By the end of the game, Harbaugh said Pitta was no longer experiencing symptoms.
Pitta has practiced all week on a limited basis.
"You don't want to miss a game in this business," Pitta said. "You want to be playing and I'm excited to be able to do that."
Despite being shaken up for the past two games, Pitta said he'll have no hesitancy about contact and isn't worried that he's more susceptible to a concussion going forward.
"There's not really a lot you can do to avoid some of those collisions," said Pitta, a California native who will have several family members attending Sunday's game. "It's part of the risk of playing football. Everybody understands that. You can't think about it. You just got to go out and play. Whatever happens happens."
Meanwhile, defensive end Pernell McPhee expressed hope that he might be able to return for Sunday's game after being sidelined for the past three games with right knee and thigh injuries. However, he's listed as questionable on the injury report.
Cornerback Chris Johnson (strained hamstring) is doubtful.
"I feel like I could go out and compete, but it's all [coach John Harbaugh] his decision," McPhee said. "He's going to make the best decision. He knows where I'm at and he knows where I'm at. He knows the right decision to make. I feel better about my chances."
McPhee had claimed to be 100 percent last week heading into a 13-10 win over the Pittsburgh Steelers, but later Harbaugh acknowledged that there wasn't a chance that the second-year defensive lineman would play.
"You could call it what you want," McPhee said. "I ain't been out there on that field scrapping with anybody. Mentally, yeah, I'm 100 percent. Physically, I don't know where I'm at until I really get out there and have some contact. Other than that, I'm all right."
Jah Reid has been practicing at left guard with the first-team offense all week and is slated to start again. "Oh yeah, I'm looking to improve every week," Reid said. "I take what happened to me the first game and what happened to me and improve on it. I made some mistakes and I want to play a lot better this week." The Chargers may play without starting left guard Tyronne Green, who has not practiced all week because of a hamstring injury and is listed as doubtful. Rex Hadnot is Green's backup. Defensive tackle Aubrayo Franklin, another former Ravens player currently with the Chargers, was limited by a knee injury for the second consecutive day and is questionable for Sunday. A pair of Chargers starters -- right guard Louis Vasquez (ankle) and strong safety Atari Bigby (shoulder) -- fully practiced Friday and are listed as probable. Punter Mike Scifres (right ankle) fully participated for the third straight day and is also probable. Punt returner Eddie Royal (hamstring) is out. Starting free safety Eric Weddle is listed as Royal's backup, but the Chargers could turn to former Ravens cornerback Chris Carr, who is already the team's primary kick returner.
Baltimore Sun reporter Edward Lee contributed to this article.Copyright © 2015, The Baltimore Sun