We hope he's okay...
Richard Simmons went to the hospital Monday for "severe indigestion" ... according to his rep.
Richard had been battling "discomfort while eating" for several days, and finally decided to get treatment at a hospital on Monday.
This is the second time in the last year Richard's had to leave his home -- where he's been sheltered for years -- for hospital care. Last summer, he was at Cedars-Sinai for 3 days after his housekeeper said he'd become incoherent.
His people said that was a case of dehydration ... which seemed weird for several days of treatment.