(CNN) The maker of a little red pill intended to treat a rare condition is raking in hundreds of millions of dollars a year as it aggressively targets frail and elderly nursing home residents for whom the drug may be unnecessary or even unsafe, a CNN investigation has found.

And much of the money is coming straight from the federal government.

The pill, called Nuedexta, is approved to treat a disorder marked by sudden and uncontrollable laughing or crying — known as pseudobulbar affect, or PBA. This condition afflicts less than 1% of all Americans, based on a calculation using the drugmaker’s own figures, and it is most commonly associated with people who have multiple sclerosis (MS) or ALS, also known as Lou Gehrig’s disease.

Nuedexta’s financial success, however, is being propelled by a sales force focused on expanding the drug’s use among elderly patients suffering from dementia and Alzheimer’s disease, and high-volume prescribing and advocacy efforts by doctors receiving payments from the company, CNN found.

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