The Minister for Justice has said he intends to introduce tougher legislation on drugs- and gun-related crime after a new report highlighted the growing extent of drug abuse across the country.
Mr McDowell said he would introduce stronger laws and minimum sentences to deter criminals from getting involved in the supply of illegal substances in the wake of the findings.
But he also insisted the gardaí are tackling the problem.
"Gardai are winning the war on drugs, the number of drugs seizures are up," he said.
"There is a very determined effort on the parts of drugs dealers to supply these goods of death to vulnerable and marginalised people right across Ireland and I intend stiffening up the law."
Mr McDowell claimed there was a strong link between drugs and gun crime. "There is a direct relationship between firearms and the drugs trade. It must be confronted. There is no room for ambiguity."
The all-Ireland report showed drug use is becoming an increasing problem outside main cities, with cannabis by far the most commonly-used drug.
Almost 8,500 people were interviewed for the Drug Prevalence Survey, commissioned jointly by the National Advisory Committee on Drugs (NACD) in the Irish Republic and the Drug and Alcohol Information and Research Unit (DAIRU) in Northern Ireland.
It found that the number of people who used illegal drugs was highest along the east coast. Cannabis was the main illegal drug consumed, with rates at least twice as high as those for other illegal drugs. The lowest rate of recent illegal drug use was in the North Western Health Board area, which stretches from Donegal to Sligo, at 3 per cent.
The highest was in the Northern Area Health Board in north Dublin where 8 per cent of respondents used drugs. Drug use was higher among men than women and higher among young people than older people in the vast majority of areas.
Additional reporting: PA