They never give me trouble, regardless of what the prescription is. I've never been ID'd for it when I pay cash, not once, to make sure that I'm the patient whom the controlled substance was prescribed to.
Last time, I paid with AMEX. The pharmacist technician got in my face about showing them the ID for AMEX, not to ensure I'm the patient whom the DEA schedule III narcotics were prescribed to.
I was asked for ID. I asked why. They said "because you're using a credit card and they're concerned about protecting me". I said "protecting me whatever, you're concerned about protecting your own flowers".
Conclusion: the COSTCO pharmacy apparently don't give a damn who uses who's prescription, as long as they're paid for it. They're more concerned about unfounded fear that they might get a charge back from a stolen credit card.
Another shady thing about COSTCO. They'll require you to sign the HIPAA thing to pick up the prescription, saying that you've read the blah blah blah documents ordering you to "just sign it" and when you ask for the said documents, they don't have it available! WTF?
SO DID YOU BEND-OVER AND SHOW IT

Did you bend-over and show it, or did you bend-over and take it? Next time simply call 1-800-VISA-911. They will walk the violating cashier step-by-step through proper card acceptance procedure.
CREDIT CARD SIGNATURE IS ALL THE ID NEEDED
When you pay for merchandise with a Visa card, MasterCard, or American Express any store that accepts these cards should accept yours too, no questions asked. It's part of the deal that merchants agree to when they become participating members.
They must check your signature and the card - electronically or by telephone - to be sure it's valid. Once the answer comes up yes, they can go ahead and charge. They can't ask you for any further identification - not a license plate number, Social Security number, proof of address, phone number or photo ID.
Your personal ID isn't needed because Visa, MasterCard, and American Express all guarantee payment on cards that have been properly checked. If the issuer mistakenly authorizes a sale on a bad card, it should make good. MasterCard says that merchants receive instant settlement. The contract MasterCard merchants sign specifically prevents them from asking for personal ID.
Unfortunately, not all merchants play by the rules. Some, apparently, haven't read them.
WHAT YOU CAN DO
MasterCard wants to hear about merchants who break their rules. Send the name and address and an account of what happened to MasterCard WorldWide 2000 Purchase St. Purchase, NY 10577 or call 1-800-300-3069. The merchant's bank will get a stiff letter, ordering it to investigate and bring the offending store into line - or pay a $2,000 fine. You may also report violations online:
http://www.mastercar...violations.htmlVisa enforces the same rules as MasterCard. "When we hear about a violation, we ask the bank that signed the merchant to get together with the merchant and see that the practice is stopped," Visa representative states. Violations of Visa’s Operating Regulations result in fines of no less than $5,000. To report a merchant, write to Visa Inc. P.O. Box 8999 San Francisco,
CA 94128-8999 or call 1-800-VISA-911.
American Express also prohibits merchants from asking for IDs. "All a merchant is supposed to do is take an imprint, make sure the signature matches and swipe the card through the terminal, to get authorization." Report violations to: American Express P.O. Box 297812
Ft. Lauderdale, FL 33329-7812 or call 1-800-528-4800 or report online:
http://americanexpress.com/yourchoice