McHugh will not undergo surgery at this time, but he will be reevaluated after the six-week period.
"We decided to give it six weeks to see if we can quiet down some of the inflammation and stuff that's in there right now, and hopefully get a little stronger and be ready to go," said McHugh, who began the season on the 10-day disabled list. "I don't think there's any measure of relief when you know you have to be shut down for a while. As a competitor, you want to be out there, you want to pitch, you want to help the team.
"We've been reevaluated. We know what it is, we know what it looks like. So I don't think there's any concern of it being worse than what we already know."
McHugh, 29, said he will remain in Houston and not accompany the club to Seattle for its first road trip of the season. The plan is for McHugh to stay in contact with trainers while working through his rehab program.
With McHugh, who threw 184 2/3 innings last season, out for an indefinite period, Houston's rotation consists of Dallas Keuchel, Lance McCullers Jr., Charlie Morton, Mike Fiers and Joe Musgrove.
"He's a part of our team, and someone we expected to be available," manager A.J. Hinch said. "It's a setback for us, but luckily we came into this season with an extra starter. We believe in the five guys we have out there, so we'll try to get him right and continue to go forward with the guys we have.
"Anytime you take a guy away, it hurts, but it's a reality. We have some guys in the Minors that will protect us if we need it. We have guys in the bullpen that have started before. We just need to get it right."
McHugh, who has never had previous elbow issues, was placed on the DL with tendinitis in his right shoulder when the season started. He exited his first rehab start with Triple-A Fresno on Thursday after one inning because of discomfort in his throwing elbow.
"I felt some elbow discomfort, tightness, after the first inning, so we decided to shut it down," McHugh said. "I'll have to rearrange my mindset now, knowing the team looks a little different now. I'll be prepared every day, I'll be rehabbing my tail off and making sure that when my time does come around, I'll be able to help, whether it's midseason or whatever."
In his short rehab start, McHugh allowed three runs on three hits and a walk in a 27-pitch first inning. He isn't sure what caused his elbow problem, or if it's related to the tendinitis he experienced in Spring Training.
"There's no point looking back, or asking why necessarily," McHugh said. "How is a good question, try to prevent it for next time. But we're focused on looking forward and how to get stronger."
Richard Dean is a contributor to MLB.com based in Houston.