Thousands of fake condoms and fake syphilis tests have been seized from a property in Castleford.
The Medicines and Healthcare Products Regulatory Agency (MHRA) recovered the potentially defective goods haul on May 24, as part of an international crackdown on illicit medicines.
Around 22,000 “counterfeit” Durex condoms were seized as well as 7,000 “non-compliant” syphilis test strips.
An MHRA spokesman said: “Products such as these may not offer the correct level of protection you expect and could put your health at risk.
“Those involved in the illegal supply of medical products aren’t interested in your health - they are only interested in your money.”
The raid was part of an international operation with Interpol called Operation Pangea.
The operation is an international week of action which takes place every year to tackle the online sale of counterfeit and illicit medicines, as well as highlighting the dangers of buying medicines online.
It brings together health regulators, police and the private sector from countries all over the world.
The MHRA spokesman added: “As part of Operation Pangea we have also seized a significant amount of unlicensed medicines.
“Be careful buying medicines online – only buy from a site that is registered with MHRA and displays the new EU common logo.
“MHRA will continue to track down and prosecute those involved in this trade.”
Operation Pangea first launched in 2008. More than 100 countries are now involved.