Viagra gave up its top position in Korea to its competitor Cialis for the first time.

According to industry data, sales of Cialis totaled 26.9 billion won ($23.6 million) last year, topping Viagra’s 25.6 billion won.

This is the first time that Viagra did not take the No. 1 spot in the local pharmaceutical industry since its release here in October 1999.

“With the massive release of generic products of Viagra, the product positioning has seen changes,” an official of a firm selling erectile dysfunction treatment told Yonhap News. “The fall of Viagra is not because of Cialis’ good sales but due to the introduction of generic products.”

The more affordable, locally-made products like Hanmi Pharmaceutical’s Palpal Chewable Tab came in third place, recording 22.3 billion won in sales over the past seven months. Dong-A Pharmaceutical’s Zydena Tab followed in fourth with 17 billion won in the same period.

The figures come after it was market research firm IMS Health Inc. reported in November last year that the sales of Viagra dropped by more than half with the proliferation of local generic drugs.

Its sales have been falling since its patent expired last May.

In October, Pfizer sued Hanmi Pharmaceutical, claiming that it violated the design patent for Viagra’s blue, diamond-shaped pill.

The market for erectile dysfunction treatment totaled 118 billion won in 2012, a rise from 107 billion won in 2011 and 97.5 billion won in 2010.

By Cho Ji-hyun (sharon@heraldcorp.com)