Drug and alcohol abuse is fast becoming an area of concern in India, which according to UN data has 2 million people who use opiates.
The Indian state of West Bengal has been identified in the National Health Survey as one of the pockets with the highest use in India. Although there are treatment centres dotted around the country, there is a gap between the number of centres and the prevalence of drug abuse. Many who seek treatment end up lapsing back into addiction.
Photographer Ronny Sen documents the struggles of some recovering addicts in the city of Kolkata (Calcutta) in West Bengal.
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