Britney Spears' two-year-old son was hospitalised at the weekend after suffering a reaction to something he ate, a statement on the singer's website said on Monday.

Jayden James, the youngest of Spears' two children with ex-husband Kevin Federline, was admitted to a hospital in Mississippi on Sunday before being discharged on Monday.

"Jayden James Federline was admitted to the Southwest Mississippi Regional Medical Center on Sunday, November 9th. Doctors concluded he had a reaction to something he ingested," a spokesperson said in a statement.

An update posted on the site later on Monday said Spears' son had been released from hospital.

A source quoted by People magazine said Spears' son had suffered a "terrible allergic reaction" and had "hives, was itchy and irritable".

Both Spears and her mother Lynne spent the night at the hospital.

Spears hit rock bottom in January when she was twice rushed to hospital for psychiatric treatment after losing custody of her sons to Federline but appears to have got her career back on track.