The symptoms kept Earnhardt from racing in New Hampshire on July 17.
Jeff Gordon will come out of retirement and return to Sprint Cup racing to act as Earnhardt's replacement for the next two races at the Indianapolis Motor Speedway and Pocono Speedway.
NASCAR fans will recall that Gordon has had much success at Indy, winning five times at the storied track -- including at the inaugural Brickyard 400 in 1994.
In terms of Earnhardt's health, reports have indicated that he has been battling balance problems and nausea -- possibly from a pair of back-to-back crashes in Michigan and Daytona.
"(My doctors) can give me a lot of exercises that retrain my brain to handle what I need to handle -- it's just going to take a lot of patience," Earnhardt said in a podcast, according to ABC News. "I take my health and quality of life as a top priority. … I am going to take this slow and strictly take the advice of my doctors."
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