OK...this is what I understand.
A hospital that is considered "disproportionate share" (DSH) is allowed to purchase drugs at a huge discount because they take on so many Medicaid/uninsured/low-income patients. They can use these medications for any patients, including those with health insurance, who are not low-income. This was meant to help them keep their coffers full.
The DSHs can purchase and dispense these same drugs through retail pharmacies in the area (any pharmacy they contract with is eligible, including independents). The pharmacy holds the drugs as a "virtual inventory".
A patient with insurance will come to an outpatient pharmacy contracted with the DSH, paying the regular copay for a certain medication. The pharmacy then gets reimbursed for the medication through the regular insurance. If the patient is considered eligible (I don't know what makes a patient eligible or ineligible), the pharmacy can submit an order to the DSH for replenishment of the medication. The DSH then sends this replenishment order to its own wholesaler via a special software designed to interface with the 340B program. The wholesaler sends the replacement stock drug to the outpatient pharmacy, but bills the DSH for the inventory. The outpatient pharmacy sends its full third-party insurance reimbursement to the special software company, minus a fee for being a contracting pharmacy. The software company then sends this full third-party insurance reimbursement, minus the contracting pharmacy fee and minus a separate software vendor fee, on to the DSH.
It's hugely stupid and complicated, and I foresee this getting regulated HARD in the near future...
http://www.nytimes.com/2013/02/13/b...l=1&adxnnlx=1381898930-tQSr40AdrLoav2ItHC5h4w