The amount of medicines and medical supplies purchased by the presidential office Cheong Wa Dae more than doubled during the Park Geun-hye administration compared to the previous one, data showed Monday.

An average of 3.95 million won ($3,380) was spent per month on such purchases during Park's presidency between 2013 and August 2016, compared to 1.87 million won between 2011 and 2012, when Lee Myung-bak served as president, according to the data submitted by the state-run health insurance review agency to the National Assembly. Park took office in February 2013.

Notably, an average of 5.71 million won was spent on the purchases that included controversial medicines, such as erectile dysfunction drug Viagra pills and placenta injections, between September 2014 and February 2016 when a doctor at the center of controversies was serving as the presidential doctor, the data showed.

The presidential office has claimed that the Viagra pills were bought to treat altitude sickness for presidential aides on Park's trip to African nations.

The data comes amid mounting allegations that Park's arrested confidante, Choi Soon-sil, at the center of an ongoing corruption and influence-peddling scandal, illicitly obtained prescriptions for the president.

After the health ministry filed a complaint, the prosecution launched an investigation into the allegations of illicit prescriptions. In South Korea, it is illegal to issue a medical prescription without diagnosing a patient -- except for some special cases such as at the request of an immediate family member. (Yonhap)