Manufacturers of drugs to treat mental health disorders look set to benefit from an exemption from a Medicaid bill aimed at cutting costs in the programme by $50 billion dollars.

Under the provision, antidepressant and antipsychotic medications will be excluded from measures that lie at the heart of the bill, namely the selection of the least expensive, appropriate treatment for patients.

The provision was included in the version of the bill that was passed by the US House of Representatives ahead of the Thanksgiving holiday last week, according to a report in the Washington Post newspaper.

Organizations representing the interests of mental health patients welcomed the move, saying that it would ensure that patients with schizophrenia and depression would receive better treatment, based on clinical rather than cost issues. But opponents said the provision was an example of the influence wielded by the Industry on the US legislative process.

Eli Lilly, which makes a number of big-selling mental health drugs including Zyprexa (olanzapine) for schizophrenia, said it was involved in lobbying for the provision along with other pharmaceutical companies and patient advocacy groups, but stressed the move was in the best interest of patients.

The Congressional Budget Office has estimated that the provision will hike federal drug spending by $125 million over five years. Meanwhile, The US Senate has passed its own budget bill, and talks between the House and Senate to reconcile the measure are expected to be contentious, according to the newspaper.

The provision was introduced into the bill by Republic Representative Steve Buyer, whose constituency abuts Lilly’s facilities in Indianapolis.