Circuit Judge Debra S. Nelson said she found no "overriding pattern of prejudicial commentary," saying media companies that objected to the order were right in saying the state failed to show there had been any prejudicial coverage in the trial concerning the shooting death last February of Trayvon Martin, 17. Zimmerman, 29, has said it was self-defense.
The judge, in her written two-page order, indicated she would consider moving the trial, question jurors one at a time and give members of the jury strict instructions about outside information.
The prosecution had been hoping to muzzle the defense, which set up a website to handle media inquiries about the case, the Orlando Sentinel reported.
Nelson also limited the number of medical records that would be available to the prosecution, saying only those related to the night of the shooting would be relevant.
The defense has released doctors' notes from the day after the Feb. 26 shooting in Sanford indicating Zimmerman was taking a number of medications for anxiety and insomnia and that he was suffering from a broken nose, cuts on the back of his head, two black eyes and back pain.
Nelson has set a tentative April date for a self-defense hearing to let Zimmerman's legal team argue second-degree murder charges should be dropped because of Florida's "stand your ground" law.
The law says a person may justifiably use deadly force in self-defense when they have "reasonable belief" of great bodily harm or death.
Zimmerman has admitted shooting the unarmed Martin but has argued he acted in self-defense, saying the teen attacked him, breaking his nose and hurting his head.
The prosecution has maintained Zimmerman profiled Martin because he was black. Zimmerman is a Hispanic-American.
The judge will determine after the April hearing if Zimmerman should stand trial. The trial is tentatively set to begin June 10.