New figures from the Central Statistics Office show that the country's trade surplus fell by 8% in the month of October, falling from €3.216 billion to €2.971 billion.
The decrease was bigger than expected by analysts.
Preliminary figures for October show that seasonally adjusted exports rose by 0.4% to €7.306 billion from €7.275 billion while seasonally adjusted imports rose by 7% from €4.059 to €4.335 billion.
The CSO figures show that the value of exports fell by 3% to €7.260 billion in October from the same month last year.
This was due to an 8% fall in exports of medical and pharmaceutical products and a 5% decrease in exports of organic chemicals.
The value of imports rose by 1% to €4.377 billion, with imports of organic chemicals jumping by 75% in October compared to the same month last year. Imports of medical and pharmaceutical products rose by 16%, while imports of petroleum and related products dropped by 31%.
Today's figures reveal that on an overall basis, the EU accounted for 57% of total exports in October, with the US the main non-EU destination as it accounted for 21% of total exports.
Meanwhile the EU accounted for 65% of the value of imports in October, with 31% coming from the UK. The US and China were the main other sources of non-EU imports.
Commenting on today's figures, Merrion economist Alan McQuaid said that weak global demand has hit Irish exports in the past couple of years, particularly on the merchandise goods side.
"But there are signs now that the world economy (including the key markets of the US, euro zone and UK) is starting to recover, which augurs well for Irish exports in the coming months. This should to some degree help offset the negative drag from the patents expiry issue on certain pharmaceutical products," the economist added.