Lilly Changes Zyprexa Labels

Eli Lilly & Co. has changed the labeling on its antipsychotic Zyprexa to avoid confusion with Pfizer Inc.’s allergy medicine Zyrtec after some patients were given the wrong drug.

Lilly said in a letter to psychiatrists and pharmacists that it had received 79 reports of such mix-ups since Zyprexa, which is used to treat schizophrenia and bipolar disorder, was introduced in 1996.

The letter, dated Jan. 26, was posted Tuesday on the Food and Drug Administration’s Medwatch website.

Patients with psychological disorders who take Zyrtec instead of their regular Zyprexa could be at risk of relapse, but Lilly spokeswoman Heather Lusk said Wednesday that the company had not received any reports of such cases.

The most frequently reported effect of the mix-ups was excessive sleepiness, which is listed as a potential side effect for both drugs, Lusk said.