You don't need a doctor to write a prescription for you to go out and buy a sofa. A pharmacy cannot by law let you refill a 30 day prescription less than about 30 days after the last time you refilled it for many medications, so you can't use your existing prescription to go stock up either.
Pharmacies seem to cheerfully dispense larger quantities even if it's not indicated on the prescription.
> But increasingly, the psychiatric association has heard from members that smaller quantities specified on prescriptions are being ignored, particularly by CVS, according to Dr. Schwartz, the group’s president.
> CVS has created a system where doctors can register and request that 90-day supplies not be dispensed to their patients. But doctors report that the registry has not solved the problem, Dr. Schwartz said. In a statement, CVS said it continued to “refine and enhance” the program.
> Dr. Charles Denby, a psychiatrist in Rhode Island, became so concerned by the practice that he started stamping prescriptions, “AT MONTHLY INTERVALS ONLY.” Despite those explicit instructions, Dr. Denby said, he received faxes from CVS saying his patients had asked for — and been given — 90-day supplies.
> Dr. Denby, who retired in December, said it was a “baldfaced lie” that the patients had asked for the medication, providing statements from patients saying as much.
