Almost 4,000 drug addicts exchanged 24,000 needles at drop-in centres across Ireland last year.
Merchants Quay Ireland (MQI) revealed the scale of the country's drug problem as demand for its services soared, with 57 needles swapped in Dublin and eight exchanged across the midlands each day.
Tony Geoghegan, MQI chief executive, said the charity also served up more than 76,500 hot meals to homeless people in the capital, while its healthcare service supported clients 3,100 times.
"These statistics are very strong indications of the increasing levels of poverty and hardship experienced by so many people," he added.
MQI's annual report for 2012 found:
:: 3,634 addicts - including 558 new service users - made almost 21,000 needles exchange visits in Dublin, up 2,000.
:: 75% of those took multiple substances, with a combination of heroin, benzodiazepines and alcohol most common, making treatment harder.
:: 2,357 inmates were supported by 27 councillors in prisons.
:: 500 drug addicts attended services in Laois, Longford, Offaly and Westmeath, which provided over 3,000 needle exchanges in the year to 130 clients each month.
:: 134 clients filled 10 detox and 27 rehabilitation beds during the year, with a high percentage from outside Dublin.
Mr Geoghegan said figures highlight the need for detox and rehab facilities across the country.
"The spread of drug use outside of Dublin was also an on-going trend with continued demand for our services at regional level," he continued.
"Our Midlands Harm Reduction Outreach Service worked with an average of 130 clients per month providing over 3,000 needle exchange interventions during the year.
"This trend was also repeated in our residential detox and rehabilitation services where 46% of those accessing our High Park residential detox to drug free rehabilitation service were from outside the Dublin region.
"Similarly, in our St Francis Farm detox and drug free residential services 25% of admissions for detoxification came from the Munster region while 30% of admissions to the drug free rehabilitation programme came from the South East Region.
There are an estimated 20,000 heroin addicts in Ireland, with 10,000 men and women on a methadone programme.
MQI provides services ranging from open access crisis intervention and health promotion services, to day support programmes, educational programmes, vocational training and settlement support services.
Mr Geoghegan said the charity, like all other voluntary organisations, are deeply concerned about the on-going cuts to social services.
"Demand for our homeless and drugs services is growing, yet finances are contracting," he added.
"We call on the Government to honour their commitment to social justice and maintain services that protect the most vulnerable men and women in Ireland."