A 51-year-old State Department employee who objected violently when charged a late fee on a rented video was unstable because he had been given the wrong psychiatric medication, his attorney said at a court appearance yesterday.

Gregory H. Stanton was accused of hitting a McLean video store owner over the head with a videocassette, then driving his car at the man, knocking him through the plate-glass front of a restaurant. Stanton fled to Amsterdam on his diplomatic passport before returning to the United States and turning himself in to police.

In Fairfax County Circuit Court yesterday, Stanton did not contest the charges. When sentenced, he faces a possible five to 20 years in jail for malicious wounding and up to five years for destruction of property.

Judge Kathleen H. MacKay revoked Stanton's $10,000 bond and ordered him held at the Fairfax jail until a sentencing hearing June 5. "This is an incredible set of facts, all to rent a video," MacKay said.

Stanton said he was "deeply mortified" and sorry for the damages and injury he had caused. "This was an aberration in my life," he said.

Thomas Abbenante argued that his client should remain free because he had no prior record and was being treated by two psychiatrists who would testify that he poses no danger. Abbenante declined to identify Stanton's mental health problem or to say what medicine he was taking at the time of the Jan. 24 altercation at the Box Office Video in McLean.

Assistant Commonwealth's Attorney Mark C. Simmons said Stanton committed a "violent, impulsive" act against store owner Hassan Mostafavi. He also noted that Stanton fled the country after the incident.

"If his bond is continued, I do not think it is right that he could ride down the same courthouse elevator as his victim," Simmons said.

According to police, Stanton argued with Mostafavi over a $4.49 late fee. He then whacked Mostafavi over the head with the video he wanted to rent -- "Nothing to Lose" -- as the men wrestled each other to the floor.

Once outside the video store at 1392 Chain Bridge Rd., police said, Stanton drove his 1993 Cadillac into Mostafavi, who had pursued him, and knocked him through the window of the Three Pigs barbecue restaurant next door.

Mostafavi, 54, who suffered cuts, bruises and a tailbone fracture, said he was satisfied with the outcome so far. "Even though the man tried to kill me, I kind of felt sorry for him to be handcuffed and put away," he said.

Stanton is on paid administrative leave from the State Department, where he has been a junior Foreign Service officer since August 1992. An official said the agency would determine what action to take about the job because Stanton was in jail.