Maryland freshman basketball player Derrick Lewis has not practiced during the past seven days because of a flare-up in a blood pressure problem he has had for years. He is undergoing tests to determine why his pressure has gone up.

Lewis, a 6-foot-7 forward from Archbishop Carroll High School, has had high blood pressure since he was 5 years old but it has been controlled by medication. Last week, after two days of practice, he was tested and, when his pressure registered extremely high, he was ordered not to practice.

"I don't know exactly what was wrong but I don't really want to talk about it," Lewis said yesterday. "I hope I'll be back by Friday."

Maryland Coach Lefty Driesell and Athletic Director Dick Dull said Lewis would be back when he is given full clearance by the doctors and not before. "We feel sure it's not a serious problem but we want to be sure and we want to be thorough," Driesell said. "He's played basketball with this through high school and there's no reason why he won't be able to keep playing basketball."

Lewis underwent tests in Baltimore on Tuesday and Driesell said he might send him to another specialist, if needed. Dull said that Chancellor John Slaughter has been kept informed of the situation as has Lewis's family.

Lewis is being counted on by Driesell as a top inside reserve. He was an all-Met player at Carroll last year, a strong inside player who is an excellent shot-blocker.