I believe the correct approach to this is as below...
First, go to your doctor and explain that you will be in the US for up to 180 days. He/she will give you a prescription for 180 days. Call your provincial medicare org. (Pharmacare in BC) and tell them that you need 6 months of meds. and that your doctor gave a prescription for 6 months. They should remove the normal 3 month limit. If you have an extended health care provider as well (Blue Cross, ex.) call them as well and explain the same thing.
Some pharmacies could possibly refuse to fill for more than 90 days or there could be errors in your online records with the province or extended health care provider. I would talk to your pharmacy well in advance to ensure there will be no issues.
For any controlled substances such as narcotics, testosterone and some others (which normally would not be available for more than 90 days), I think what you need is special permission and a prescription renewal from your doctor. He/she will set it up as needed by the provincial gov't. Then you need to take the prescription to a US doctor who will fill out a new one for a US pharmacy.
Be aware of the medications that are considered controlled substances in the US.
List here Also, some medications may not be available in the US or are under a different name so I would make sure that there are no difficulties with this. Some over the counter meds like codeine based aspirin (222) are not available in the US.
In any event, the first step is to go talk to your doctor. Also, check the US Customs information online. It is YOUR responsibility to ensure you know about all rules and regs. and any recent changes and that is even more important if you have Nexus cards (otherwise it's cause to have them taken away). Here is link to CBP on
90 day supply of meds.
