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March 23 (Reuters) - The U.S. Food and Drug Administration said it would not recommend changes to the prescribing or use of Eli Lilly and Co's schizophrenia drug after a review of two deaths.

Elevated levels of the drug, Zyprexa Relprevv, were found in the two patients who died in 2013, three to four days after receiving the injection.

The FDA said its investigation into the deaths was inconclusive. (http://1.usa.gov/1xsdbOe)

The study noted that much of the increase in drug levels could have occurred after death, explaining the extremely high blood levels of the drug found in the two patients.

Zyprexa contains the antipsychotic drug olanzapine. It carries a boxed warning, FDA's most serious type of warning, for post-injection delirium sedation or olanzapine overdose.

Lilly's earnings have suffered since late 2011, when Zyprexa, its top-selling drug, began facing cheaper generics in the United States.

Zyprexa's 2014 sales have fallen to $1.04 billion from $4.62 billion in 2011.

(Reporting by Amrutha Penumudi in Bengaluru; Editing by Sriraj Kalluvila)