ATLANTA — A federal judge on Monday rejected a Georgia inmate’s argument that his execution, scheduled for Tuesday evening, should be stayed because the state had refused to disclose details about the drug to be used in his lethal injection.

Marcus Wellons, 58, was sentenced to death in the 1989 rape and murder of a 15-year-old girl. Absent a court order issuing a reprieve, he will be the first person executed in the United States since the botched lethal injection in Oklahoma of Clayton D. Lockett on April 29.

The execution of Mr. Lockett, who writhed in apparent agony when he was supposed to be unconscious, raised new concerns about states’ lethal injection protocols, the drugs used and new laws in some states, including Oklahoma and Georgia, that keep details about those drugs secret.

The Georgia State Board of Pardons and Paroles denied Mr. Wellons’s clemency request Monday afternoon. Later, Judge Timothy C. Batten Sr. of Federal District Court in Atlanta denied Mr. Wellons’s request for a stay of execution.