The chiropractor, who never examined Ethan, told them to put honey on the wounds and give the boy oregano oil to control the behavioral issues.
The couple also gave Ethan over-the-counter medications, including Benadryl and children's Tylenol.
"They thought that Ethan was sick," defense attorney Richard Mauro said Thursday outside of court. "They believed that he was ill and they thought he had an allergy. They were giving him over-the-counter medications and they ended up harming him more than they were helping him."
Mauro said the couple were concerned with Ethan's mental state because he was repeatedly talking about an event when his father, Joe Stacy, choked Stephanie Sloop in Las Vegas in June 2009. Stephanie Sloop took her young son to a child psychologist, she told a friend in a text message shown in court Thursday.
At the end of Nathan Sloop's three-day preliminary hearing, which began Wednesday, Judge Glen Dawson will decide if there is enough evidence to proceed to trial.
Investigators believe Ethan died on May 8, 2010. Nathan Sloop on May 11, 2010 led police to where the boy's beaten body was buried in a shallow grave near Powder Mountain Ski Resort.
Thursday's testimony was much less graphic than the day before, when Layton Police Sgt. Jeff Roderick detailed how the body, wrapped in eight garbage bags, was found buried beneath layers of items that were used to "take care" of Ethan's body, including a broken hammer, a shovel and a bottle of lighter fluid.
Nathan Sloop told investigators that he used a hammer to disfigure the boy's face and teeth after Stephanie Sloop told him she was worried about dental records being used to identify her son.
In addition to aggravated murder, both Stephanie, 30, and Nathan Sloop, 34, have been charged with intentionally inflicting serious physical injury on a child, obstructing justice and abuse or desecration of a human body. Nathan Sloop is also charged with damaging a jail cell for kicking the holding cell at Layton Police Department while he was waiting to be questioned about Ethan's body.
Seven aggravating factors are listed in charging documents connected to the murder charge, including child abuse, desecration of a human body, that the victim was under the age of 14, and the crime was committed in an "especially heinous, atrocious, cruel or exceptionally depraved manner."
Prosecutors have filed their intent to seek the death penalty for Nathan Sloop.
Thursday's cross-examination of Roderick focused on what medical treatments the Sloops sought for Ethan in the days before his death, along with the large amount of prescription medication that Nathan Sloop was taking in the months before Ethan died.
According to a Department of Professional Licensing document, which tracked all of the narcotics that Nathan Sloop was prescribed, he was given 4,146 pills in an 11-month period.
Nathan Sloop was prescribed almost 650 pills in March and just under 500 pills in April. In the first 10 days of May, between 350 to 370 pills were prescribed to the man.
Mauro said the man's prescriptions included Lortab, Valium, Percocet, an antihistamine and anxiety medication.
Nathan Sloop told investigators that the pain pills were meant to treat back pain.
Transcripts from police interviews with Nathan Sloop were read in court Thursday. On at least six occasions during the interviews, Nathan Sloop told police he would take responsibility for some of the bruises found on Ethan that were inflicted by his wife because he did not want to see Stephanie Sloop go to prison.
"Look, I'll say whatever," he told investigators, crying. "Just let me talk to Stephanie. Let me kiss her, let me hold her, let me pray for my forgiveness from her and then send me the f- away."
Charging documents allege the Layton couple engaged in multiple acts of "severe abuse" between April 29 and May 8 in 2010, which led to Ethan's death, including "beatings, burning, drugging, isolating, malnourishing, leaving the child alone and unattended while suffering, and refusing to seek vital life-sustaining medical attention."
According to police probable cause statements, Stephanie Sloop said she knew Ethan needed medical attention after an initial May 5 disciplinary beating by Nathan Sloop, but that she was afraid Sloop would harm her, too, if she acted.
She told police that Ethan became "extremely ill," would not eat and was given Benadryl to keep him quiet. She also told police that on May 7, Nathan Sloop told her Ethan had burned himself in the bathtub on his feet, legs and buttocks by turning up the hot water when Nathan Sloop left the bathroom. But Nathan Sloop admitted to police that he had scalded the boy, according to testimony.
The couple who told police they left the injured boy in a locked bedroom while they got married on May 6 reported Ethan missing on Mother's Day, May 10, after discovering the boy was dead. But after a 12-hour search, police say the couple confessed to burying the boy on a mountainside in Weber County.