Many of India’s regulatory and IP issues have left Big Pharma scratching its head, but the country’s recent decision to ban three drugs—with little-to-no explanation given—has even local drug makers confused.

Two weeks ago, Indian regulators banned Takeda’s diabetes treatment Actos and two other older treatments, the anti-depressant Deanxit and painkiller Analgin. The New Delhi Business Standard reported that the ban was “triggered by the health ministry’s commitment to a parliamentary committee that it would immediately suspend medicines not allowed for sale in major international markets.”

If those reports are true, the move could set a new precedent for how Indian regulators will make rulings on new and existing drugs based on their status in mature markets, one expert says. Actos is currently banned in Germany and France and was slapped with a black-box warning in the US for possible bladder cancer risk. Before the ban, the drug was available in India as a generic from various manufacturers: Dr. Reddy’s, Sun Pharma and Ranbaxy.

The move follows the April 1 decision by the Indian Supreme Court to deny a patent for Novartis cancer blockbuster Glivec (marketed as Gleevec in the US).

Stephan Danner, a partner in Booz & Co.’s global health practice and co-author of a recent survey on emerging markets, told MM&M, “This decision was another step to make life for Big Pharma more difficult in India than it is already now. From the perspective of pharma, this doesn’t make the market as attractive as other markets.”

That goes for local drug makers, too. Sun Pharmaceuticals and Lupin are crying foul, claiming the regulator, the Drugs Controller General of India (DCGI), issued the bans without proper consultation with the Drug Technical Advisory Board. D.G. Shah, secretary general of the Indian Pharmaceutical Alliance, said, “We are demanding a review. A ban has to be based on science and scientific data.”

If the ban stays in place, Indian companies could lose 700 million rupees ($11.5 million) in sales. Dr. Reddy’s, Sun Pharma, Lupin and Ranbaxy all stand to be affected. Lupin group president Shakti Chakraborty, told The Business Standard, “This drug is in use in most advanced markets of the world, be it the US, Japan, or the UK. I believed the DCGI has invited comments and responses from the industry, and it should come up for review.” Lupin currently sells various combination of pioglitazone, the main ingredient in Actos.

For Big Pharmas looking in, Danner suggests they continue to be more “proactive in their partnerships with government and local drug makers to avoid similar top-down, enforced [decisions], like we saw with Glivec.”

Regardless of its regulators’ eccentricities, Danner still believes India is too valuable a market for industry to turn its back on. “I still have a hard time seeing Big Pharma drastically pulling out of [India]. I don’t see that happening, but I am seeing decisions—like this one— which further pushes the limits of what will work in India.”