tricomb
Bluelight Crew
You need to let your doctor know that you have a medical marijuana card. As long as you are upfront and don't try to hide anything, there shouldn't be an issue. If they make you choose between mmj and them, you should find somewhere more sympathetic.
^ This. All I had to do was show my pain management doctor my original 215 script and the only information he wrote down was the expiration date, and he said "Show me the new one at this time next year."
From a medical standpoint, Marijuana is tolerated, especially in California, and the drugs they want to make sure you're not abusing are the high-risk ones (cocaine, methamphetamines, heroin, etc.) that could interfere with your judgement/ability to dose yourself with opioids.
Read the paperwork you have to sign with your clinic, it will explain all your rights and the rules you must follow, (usually subjecting to random UA. Every clinic I've gone to said they were going to do random UA and never did) it's mostly legal mumbo-jumbo, but it's VERY IMPORTANT.
Always read EVERYTHING before you sign it, especially the fine print. Get out those reading glasses, make sure you agree to the terms, it's a legally binding contract.