NZ Muscle is pulling batches of creatine supplements from sale because the products contain a milk allergen that was not disclosed on packaging.

The recall covers NZ Muscle Creatine (unflavoured) and No Brand Creatine Monohydrate, both with a best-before marking of JUN27. The supplements were available through certain retail stores and online channels across New Zealand in 200g, 500g and 1kg sizes.

NZ Food Safety opened an inquiry into the company on Tuesday after social media complaints emerged about the firm's food safety standards. Acting deputy director-general Mike Inglis said the issue is that packaging fails to alert people who must avoid milk because of allergies.

"Food safety officers are investigating NZ Muscle following complaints," Inglis said. "Our focus right now is to ensure that consumers are protected and affected product is efficiently removed from the supply chain."

The agency will partner with NZ Muscle to determine what caused the labelling failure and stop it happening again, and will review other allegations raised about the business. The supplements have been pulled from retail shelves, though some product was shipped to Australia as personal imports.

People with milk allergies are advised to return the products for a refund or discard them. Food Safety has received no reports of allergic reactions associated with the product, but anyone who has consumed the supplements and is worried should contact their health professional or call Healthline on 0800 611 116.