Sen. Chuck Grassley is seen during votes in the Capitol, Dec. 5, 2023. (Tom Williams/CQ-Roll Call via Getty Images)

(WASHINGTON) — Sen. Chuck Grassley, the oldest serving member of the United States Senate, is receiving antibiotic infusions at a hospital to treat an infection, according to a statement from his office.

The Iowa Republican is 90 years old.

His office says the senator is in good spirits and will return to work “as soon as possible following doctors’ orders.”

Intravenous infusions of antibiotics are usually used for a serious infection or one that can’t be or was not successfully treated with oral antibiotics.

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