Malaysia made its largest single drug bust ever when it seized RM14 million worth of fake sex pills labelled "Miagra".

Health Minister Chua Soi Lek said his ministry's enforcement team and customs officials last week detained a container from Singapore loaded with 142 boxes containing 1.4 million Miagra capsules.

"Initially, the owner of the container claimed that they were vitamin pills," Chua was quoted as saying by state news agency Bernama .

"On inspection they were found to be fake and unregistered drugs which contained Sildenafil of less than 50 milligrams per capsule, the same as in the Viagra brand of drug," he said.

"It is a fake drug, as it can be said to be similar to the original (Viagra)," he said.

The counterfeit drugs, closely resembling the blue pills of the genuine Viagra brand, were destined for Malaysian and Thai markets, Chua said.

The Star daily reported that the ministry was still conducting investigations to identify the company involved in the scam.

If found guilty, the culprits could face a fine of RM50,000, a sentence of three years in jail, or both.