Shares in pharmacies supplier Sigma Healthcare have plunged after the company warned that underlying earnings will come in below market expectations, citing “challenging” industry conditions.

Sigma expects full-year earnings for the 2018 fiscal year of around $90 million, compared to current market consensus of around $95 million.

In an announcement to the ASX on Friday, the company also said it now expected first-half earnings to come in around $44 million.

Shares in Sigma were down 8.1 per cent to 85.5 cents at 1301 AEST.

Sigma said it had taken steps to lift its sales performance and grow its market share, to overcome “general market conditions”.

Chief executive Mark Hooper said the business was confident of improvement.

“Sigma delivered above guidance growth in FY17 and remains confident that our business strategy and increased investment in infrastructure will deliver growth and efficiency improvements beyond the current year,” he said in the statement.

The company is due to announce its results on September 7.

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