The so-called "two-invoice system" refers to the sale of drugs from production enterprises to the circulation of enterprises to issue a special VAT invoice or ordinary VAT invoice, the circulation of enterprises to sell to the medical institutions and then issue an invoice. Industry sources, in the past, the drugs from the production chain to the hospital through seven or eight or even more than ten drug distribution enterprises hand, layers of price increases, so that the price of drugs doubled; and the "two-invoice system" will compress the price of the inflated space, help to realize the price of drugs transparent.