DISTRAUGHT over her dad’s fading health, bipolar pop princess Britney Spears is fighting for her sanity in a psych ward where she’s heavily medicated and could face brain-frying electroshock treatments, sources tell GLOBE.

The 37-year-old Toxic songbird’s family checked her into a mental health clinic for a 30-day stint after she bizarrely started calling herself “Britney Jean,” dishes a snitch. The former Disney kid took a dramatic turn for the worse after her February Las Vegas residency, Britney: Domination, at the Park MGM resort was canceled.

Her “indefinite work hiatus” came after her father Jamie’s colon ruptured late last year. He was hospitalized in Louisiana for 28 days — thousands of miles away from his troubled daughter.

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