Nick Reiner's weight gain and his schizophrenia medications being switched up may have led to him murdering his parents, Rob and Michele Reiner.

According to TMZ's new documentary The Reiner Murders: What Really Happened, which aired on Friday, January 9, the 32-year-old drug addict was struggling in the moments before allegedly killing the critically-acclaimed director and his wife on December 14, 2025, at their Los Angeles home.

Nick Reiner Was Previously Diagnosed With Schizophrenia

Source: MEGAA change in Nick Reiner's medications may have fueled his parents' brutal killings, a new documentary claims.

Sources revealed in the publication's newest documentary how Nick was diagnosed in 2020 for schizoaffective disorder. The mental illness includes symptoms such as delusions, hallucinations and severe depression.

He had also been diagnosed just weeks before his parents' deaths with schizophrenia.

The medications he was taking for the disorder allegedly made him "erratic and dangerous."

Nick's Behavior Was Becoming 'Alarming'

Source: @michelereiner/InstagramNick Reiner was diagnosed in 2020 for schizoaffective disorder.

Months before the killings, Nick was put on medications that aided in stabilizing his condition. A few weeks before he went on his alleged murderous rampage, he reportedly asked his doctor to do something about his weight gain, which is a common side effect from the meds. His physician later changed the pills to help him. Insiders divulged that Nick's behavior was becoming "alarming" in the month before the slayings. Rob and Michele were reportedly aware of this and were concerned about what to do.

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Nick's Lawyer Withdrew From His Case

Source: @michelereiner/InstagramMonths before the killings, Nick Reiner was put on medications that aided in stabilizing his condition.

Nick had been seeing a psychiatrist before the killings, but doctors "did not attempt to place Nick on a temporary psych hold to stabilize him.""Nick is not competent to stand trial," another source told TMZ. The Being Charlie filmmaker was arrested hours after Rob and Michele's deaths and is facing two counts of first-degree murder.

He was supposed to be arraigned on January 7; however, his lawyer Alan Jackson left the case before he was able to stand in court.

Source: @michelereiner/InstagramNick Reiner was arrested for his parents' murders on December 14, 2025.

A public defender has since taken over Nick's case. Nick also allegedly doesn't understand why he's in jail and believes there's a "conspiracy" against him.

According to TMZ, he's been acting delusional due to the change in his medications, and it is making him suffer a "complete break from reality."Another insider previously revealed that his family is done with him, adding, "they realized they cannot support him anymore - not financially, not emotionally, not morally.""They won't bankroll chaos," the source told Rob Shuter's Substack. "They loved him once. But what he did, what he became... it was monstrous. They can't protect him anymore, and they can't keep funding his destruction."