Medsafe has recalled four sexual performance drugs that contain undeclared prescription medicines.
The agency advises customers to immediately stop taking the products, marketed as So Hard for Men, Pulse8 for Women, The Rock and Tonic 66, and seek medical advice if they have felt unwell.
Medsafe says some of the ingredients in the drugs interfere with certain heart medications and their use can be harmful or even fatal.
The four products are sold in adult shops and over the internet as products that can enhance sexual performance or treat erectile dysfunction.
All known retailers and distributors have been told to remove the products from their shelves.