A former Viginia prisoner who was give massive amounts of an antipsychotic drug, became paralyzed and then developed maggot-infested bedsores because he went untreated in a prison hospital, was awarded $518,000 yesterday from state prison officials.

The out-of-court settlement, announced in Richmond by lawyers for the Washington-based National Prison Project, was said to be the largest sum ever granted to a prisoner for mistreatment in an American prison.

The injuries that Harry Tucker, the 43-year-old former prison inmate sustained, were so severe that he has to undergo a series of painful skin grafts, loss of both hips and is now confined to a wheelchair.

Tucker's lawyers hailed the award as a milestone in prisoner rights and said it will place prison officials "on notice" about the risks they run by ignoring the needs of their inmates.

Shortly after U.S. District Judge Robert R. Merhige Jr. approved the settlement, the Virginia chapter of the American Civil Liberties Union, an affiliate of the group that handled the case, disclosed it had petitioned Gov. John N. Dalton to pardon Tucker as "a humanitarian step."

Tucker, who was granted parole from a life prison sentence in November 1977, said yesterday as he appeared at the federal courthouse that his award was "suitable." His legs withered and still "painful," Tucker said softly, "I really have been through a lot."

What Tucker, convicted in a Southside Virginia court in 1964 of breaking and entering with intent to commit rape, underwent in the Virginia prison amounted to "the grossest form of neglect and mistreatment," lawyer Steven Ney said.

Tucker's medical problems began in November 1976 when he was given Prolixin, a poweful behavior modifying drug, by a state prison physician who stated under oath that he "had no knowledge of the purposes, effects or side effects of the drug," Tucker's lawyers said. The physician also stated during deposition that he had no medical understanding of schizophrenia, Tucker's condition, and prescribed the drug for Tucker on the advise of another doctor. Except for the schizophrenia Tucker was healthy at the time, his lawyer said.

"To make matters worse, Tucker was given unprescribed and excessive amounts of Prolixin by untrained and unlicensed prisoners who worked in the hospital on each of seven consecutive days," the National Prison Project said in a statement. Prison doctors did not review Tucker's case then and "this gross error" went undetected, the statement said.

Tucker slept "for almost a week" without examination by prison doctors and in December as his reaction to Prolixin intensified, he was given still more of the drug, the lawyers said. "He became catatonic-like in appearance, unable to move, withdrawn and was not eating," the statement said.

Placed in an isolation cell at the prison hospital, Tucker went untreated and his condition continued to decline, his lawyers said. Both his arms and his legs became paralyzed and he was sent to Central State Hospital, a state institution in Petersburg where doctors once again failed to diagnose his condition.

At Central State, Tucker was given another antipsychotic drug, Stelazine, the side effects of which are similiar to Prolixin, the lawyers said.

In February 1977 Tucker, then totally disabled, was returned to the penitentiary hospital in Richmond despite subsequent testimony by hospital doctors that the hospital lacked both the necessary staff and facilities to properly care for Tucker.

Left unattended in his paralyzed state for more than six months, Tucker developed "enormous bedsores" which became infected and maggot-infested, according to Nye.

Finally, Tucker was transferred to the Medical College of Virginia in September 1977 where he underwent a series of skin grafts and had to have both hips surgically removed. He continues to require 24-hour assistance, said Nye.

Tucker is planning to return to his family in South Boston near the North Carolina border within a few weeks, according to Nye. He worked as a laborer there before his arrest 14 years ago.

Under terms of the settlement, Tucker's share of the award, $440,000, will be placed in a trust fund. About $18,000 will be used to pay court costs and the remainder will go to the National Prison Project, Nye said.

The state's loss is covered by insurance, lawyers said.

A spokesman for the Virginia prison system declined to comment yesterday on the settlement and turned aside questions as to whether the prison system had corrected any of the alleged abuses that led to Tucker's condition.