Philly-based rapper Freeway, said Thursday that he needs a transplant after kidney failure sidelined him in September. 

And he’s getting serious about spreading the message that kidney disease is dangerous.

“It’s definitely a drastic change in my life,” he said. 

The hip-hop star behind “What We Do” will host the 14th annual Philadelphia Kidney Walk this weekend to help bring awareness to the disease, just weeks after a seven-day stay in the hospital forced him to cancel his appearance at Freefest.

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For about a month leading up to his performance at Made In American, he said he was feeling very tired. 

"I wasn’t myself,” Free said. “Before I went on stage, I said ‘I don’t know if I can do it.' That’s not in my character.”

He did the show, but got himself to his doctor that he sees for high blood pressure and diabetes. A few days later, he got a call about his blood. Doctors wanted him to go to an emergency room. 

That was September 17. He was on dialysis the next day. 

Free said he felt better pretty quickly, but doctors wanted him to take it easy. 

The ordeal led — perhaps amazingly quickly — to a partnership with the National Kidney Foundation, where there is hope that Free can bring awareness to a demographic they haven’t been able to reach before.

“We’re planning on keeping this relationship together to take this to a national level,” said Loren Yakopcic, a development director for the foundation’s Delaware Valley chapter.

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Arguably, Free's most famous lyric is about desperation that leads to crime and talks about hustling ‘till the sun comes up. Does it seem strange for him to participate in a charity walk?

“Not really,” he said. "I do stuff for the community all the time. I talk to kids, I go places. I marched in Baltimore when Freddy Gray got killed. It’s not too far fetched for me to do the kidney walk. It’s part of my life now.”

That life means dialysis on Mondays, Wednesdays and Fridays. If he wants to tour outside of the weekends to promote his upcoming album Freedom, he’ll have to plan where that will get done. 

But he’s urging people to stay close with their doctors.

"If I would have caught it earlier, I might have been able to manage it,” Free said.

The Philadelphia Kidney Walk is expected to draw 4,000 people this weekend and organizers say it raises money for research and awareness. Registration begins at the Philadelphia Museum of Art at 8:30 a.m. on Sunday. The walk begins at 10:30 a.m. There’s no fee for walkers, but they are encouraged to donate.