The recent deaths of 15 people linked to a small pharmaceutical factory in the eastern city of Raipur have highlighted how easily adulterated drugs can enter India's huge healthcare system.
Experts say the government is underestimating the scale of the problem, hampering efforts to rein in abuses in one of the world's biggest markets for counterfeit and substandard drugs.
Stuffed in glossy packaging and sometimes labelled with the names of legitimate companies, fake drugs are commonly passed off to Indian consumers as genuine and sold in developing nations around the world.
Estimates vary of the number of fake drugs in India. According to an estimate from the World Health Organisation, one in five drugs in India is fake or faulty. The Indian government, by contrast, says the figure is closer to 0.3 percent.
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Regulating a sector beset by bribery, collusion, cartels and other coercive practices poses a challenge for Indian government officials when selecting which manufacturers to buy from, a 2013 report by the United Nations Office on Drugs and Crime found.
India's drug regulator was criticized for only having 124 employees, according to a parliamentary report two years ago. By comparison, the drugs regulator in the United States, where the population is four times smaller, has about 14 500 employees.
"States procure medicine through a tender and the manufacturers that bid the lowest quote win the order to supply, regardless of their manufacturing process or distribution systems," said Bejon Kumar Misra, head of Partnership for Safe Medicines India, a non-governmental organisation.
Complacency a factor
But G.N. Singh, the Drugs Controller General of India, said quality and safety came before price in the tender process.
"If the drugs are found to be substandard, we will suspend the license of the manufacturer," he said.
Some experts fear complacency is a factor.
"There is a lack of regulatory oversight and if you are cutting the costs right down to the bone, then sometimes you are cutting too far," said Roger Bate, an academic at the American Enterprise Institute in Washington.
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"I don't see it getting better, because the government doesn't admit there is a problem, let alone trying to address it," he added.
The central government might be spurred into action by the latest scandal which has hit headlines at home and abroad.
Thirteen women who attended a squalid sterilisation camp in eastern India last weekend have died, and the prime suspect is a batch of pills supplied by a small drugs factory, Mahawar Pharmaceuticals, located in Raipur, state capital of Chhattisgarh, one of India's poorest regions.
The owners of the plant deny all wrongdoing.
Two more deaths underlined suspicions that it was drugs, not dirty equipment or botched operations, that were to blame.
One of the two, 80-year-old Anjori Maheshwari, arrived at a hospital complaining of fever and dizziness. He was clutching a strip of pills from the same batch of antibiotics used by the women at the sterilisation "camp". A day later he was dead.
"The doctor said my father died because of this medicine," Chuni Lal, the man's 38-year-old son said, as he wept on the veranda of his home. "What can we do, we are poor people?"
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The state government has banned the sale and distribution of all medicines from Mahawar.
Reliable estimates of the number of fatalities from tainted drugs are hard to come by. In one of the worst cases, counterfeit drugs were blamed for contributing to the deaths of more than 300 infants in Kashmir in 2012 after they were given medicine at the state's main paediatric hospital.
"It is an easy crime because it is impossible to tell there is a problem with the drugs just by looking at them," said Anil Bansal, a doctor at the Delhi Medical Council. "As the industry becomes more lucrative, the problem is getting worse."
(Additional reporting by Andrew MacAskill and Tanya Ashreena in New Delhi and Zeba Siddiqui in Mumbai; Editing by Mike Collett-White)
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Image: Medical package from Shutterstock