(CBS) -- For years, Marc Falkowitz made a monthly pharmacy trip to buy medication for his aunt.
When he complained about the cost of the co-pays, the pharmacist at a major national chain whispered an alternative-check area pharmacies' cash prices through comparison websites like goodrx.com.
He did, and found the same seven drugs that cost nearly $160 in co-pays available for just $62 cash, without insurance, at Philadelphia's Friendly Pharmacy.
"It's shocking, It's outrageous. Why do you have insurance?" Falkowitz said.
Pharmacies can sometimes offer a lower cash price because they don't always pocket the co-pay.
"It's what we call a clawback," says pharmacist Tom D'Angelo.
A PBM-or pharmacy benefit manager-negotiates rates between pharmacies and insurance companies. They don't want pharmacies undercutting the deals, so they contract bar pharmacists from actively offering a cash sale.
D'Angelo can talk because he now runs a compounding pharmacy not subject to non-disclosure agreements.
Lawsuits are challenging clawbacks and some states have outlawed them. But benefit managers insist pharmacists are empowered to charge the cash price if it's lower.
The takeaway for consumers: Ask your pharmacy for their cash price-and consider shopping around.