Your "friend" should talk to a lawyer right away. If police are asking questions about this the only thing that your friend should say is, "I don't want to talk to you. You can't search without a warrant. If you have a warrant I want to see it. I also want a lawyer appointed to represent me."
If your friend has already violated these rules then the answer to your question is generally 0-10 days jail for possession, possibly some concurrent time for falsification of prescription drug records, and substantially additional time if there is a delivery or resale aspect to the case. Of course, all of it will depend on a number of factors like what your friend's criminal history is, what police think they know right now, etc. The main thing is for everyone to know and assert their rights (i.e., shut up) and talk to an experienced criminal defense attorney immediately.
This post is offered as general information and is not intended as legal advice. This information does not in of itself create any attorney-client relationship.