system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does it take so long for the pharmacy to fill my prescription?
gpt
* A lot of times the pharmacist is looking up what other medications you're on to make sure they don't have a bad reaction with each other. (For example, If you're on medication A, and get prescribed medication B, the pharmacist check that A and B together don't cause a problem). If a reaction is found, the pharmacists may have to look up a substitute or call your doctor.

* The pharmacist may be looking up a generic so you get a cheaper drug.

* Some medications are made on the spot (very few, but they require attention)

* Other people came in before you, and you're waiting for the pharmacists to get through the backlog

* There is a TON of paperwork involved, from DEA forms, to insurance, to pharmacy policy, etc.