A Fairfax County man's class-action suit requesting $750,000 for each of the participants in Straight Inc., a national drug rehabilitation program with a Fairfax branch, was rejected yesterday by a federal judge who said the man's charges of brainwashing and harassment were an individual matter.

U.S. District Court Judge Albert V. Bryan Jr. said there was insufficient evidence to prove that the suit, filed in Alexandria last month by Fred Collins, 20, represented the wishes of more than 3,000 program participants cited in the suit. Bryan said Collins could, however, proceed with an individual suit against the program.

The ruling followed a last-minute attempt by Collins' attorney to limit the persons included in the suit to participants in the Fairfax program. "It doesn't make any difference, class or no class" action, attorney Philip Hirschkop said yesterday, "as long as we can go forward."

Ronald Goldfarb, a D.C. lawyer representing the Florida-based drug rehabilitation program, called Collins a "rebel without a constituency" and contended that "90 percent of the case was thrown out" as a result of the ruling.

Collins had charged that he was held captive in Florida by Straight counselors for 5 1/2 months last year. His suit alleged that the firm's methods included regular mental and physical abuse such as solitary confinement and lack of food.

Bryan also denied a motion by Collins to release the names of program participants. Earlier, a group of parents and participants in the Straight program presented affidavits denying Collins' charges and saying they did not want to be in the lawsuit.