When patients qualify for a medical marijuana card, they receive a prescription just like any other person would for a medication.
The prescription can be filled every week and the patient can only access the amount of marijuana listed on the prescription.
In the state where I work and live, each patient can purchase up to 2 oz of marijuana with each separate prescription. If the patient has no more room on the prescription, we are unable to sell marijuana to the person. It is state and federal law and if we get caught, there is a big fine and possible jail time, and every person working in the medical marijuana dispensary knows and understands the laws and how they work. The budtenders have to pass a test before they can work behind the counter and interact with customers. Several weeks ago, I was training a new budtender. We were working behind the counter helping an older man fill his medical marijuana prescription. Unluckily, the guy already bought the full amount of marijuana listed on his prescription and he had two weeks until the prescription renews. The budtender politely tried to explain the situation to the man, although he became angry and belligerent. I had to step in and call the security officer when the man started yelling and screaming. He had to be removed from the dispensary. He sat outside and complained for another several hours and then the officer threatened to call the police so he would leave. The entire ordeal was a good training exercise for the new budtender.