New figures from the Central Statistics Office show that monthly wholesale - or factory gate - prices decreased by 0.4% in April.
The CSO said that the annual percentage change showed a decrease of 3.8% in April, compared with a decrease of 3.3% in the year to March.
The most significant changes on a monthly basis were increases in the prices of fish and fish products, which rose by 4.8%, while basic metals increased by 3.7% and meat and meat products rose by 0.9%.
Decreases were seen in dairy products prices, which fell by -2.6% in the month.
Basic pharmaceutical products and pharmaceutical preparations were also 1.1% while other food products including bread and confectionary eased by 0.5%.
The CSO noted that the price of energy products decreased by 24.3% in the year since April 2015, while petroleum fuels decreased by 12.2%.
It also said that all building and construction materials prices increased by 1.1% in the 12 months to April.