Here's how it works: Never declare health issues on a resume, only education and work experience. For companies that drug test, it goes like this. After your interview you report to a lab to pee in a cup, same day or the next day. For what some consider more "corporate" or "professional" jobs, you will get an offer letter in the mail. If you write back accepting the job you will be expected to schedule a test before starting work. Sometimes you can stall beginning a new job for several weeks after the offer.
THERE IS NO CANNABIS PRESCRIPTION. Too many people are getting this wrong. Your doctor RECOMMENDS cannabis in order for you to get a state-issued card. It is illegal for the doctor to PRESCRIBE (schedule I drugs cannot be prescribed - by definition they have no medicinal use) - there is no prescription, only a recommendation.
At the drug testing lab, on the questionnaire mention that you take cannabis/cannabinoids. If you do not have a Marinol prescription then write-in that you have a card "medical exemption" - it's better than nothing. They always ask you to declare the drugs you have taken recently. Be honest. To declare afterward makes it look like you're hiding and makes your credibilty questionable. If it's in your system they will find it. (There are ways to flush but that's another chapter - sauna & diet are best).
The BEST thing a medical cannabis patient can do is to have the doctor write a prescription for Marinol. He can write a prescription for that but not cannabis. Marinol is THC in sesame oil, and will make you fail a drug test the same as bud, the metabolite is identical. A marinol prescription cannot be legally argued by the employer, but a medical card can. (cannabis is schedule 1 - no prescriptions, marinol is schedule 3 - prescriptions are legal).
Your doctor cannot legally write you a marinol prescription simply for the idea of passing a test, you need a medical reason. But if you tell your doctor that your other medications (painkillers, even ibuprofen) cause you nausea, and that marinol will help you with that, then you are helping protect your doctor. It's okay to mention to the doctor writing the marinol prescription that it will help you pass a test - he wants to help you, but you have to help him do things legally by telling him that marinol is for nausea (or wasting syndrome for some), not for passing tests. Cannabis doctors understand this...it's like asking for a waterpipe at a pipe shop. Asking for a bong gets you thrown out. Good Luck!
So...when you get the recommendation for the card, ask the same doc for a Marinol script to help with nausea, and that gee gosh, it will also help you legally pass your employer's test. (Assume that any job with insurance benefits will test you). MArinol cost about $15 per capsule so only ask for about 2 or 3 tabs - they are for use when the painkillers give you severe nausea. If you DO get the marinol script, you might avoid mentioning the cannabis card to the testing lab - you don't need it for a marinol script, but you might have to show the prescription or bottle. Disclose the card if you cannot get the marinol script.
In the end, expect to be rejected for medical marijuana usage even if the people trying to hire you are compassionate. Compassionate people still follow company policy and fire you, or they too will get fired. Corporations are a bitch and they care about money, and for you to test positive means you could be an insurance liability - that's how they view you. Learn the system and use it to your advantage. Corporations are more concerned about federal laws and they could care less if a state law allows something that is still federally illegal. They follow OSHA and other federal regulations, so their policies are often based on what feds say. I know this from multiple experiences and it's important you understand and pass it on. Sad but true. You will be discriminated against...it's a matter of time before the Supreme Court takes this one and make abortion legal, so to speak. You have to speak up.
With that said, today we need more activists hounding corporations to recognize and accept that medical cannabis patients are not a threat. People hiring in the corporate world have no idea how to handle it and usually ignore you, or turn you down with a form letter. We need to breed this familiarity now in order to fuel acceptance in the near future. The sooner we introduce ourselves the sooner that changes will be made. Write lots of letters, ask questions and make these people think about these new ideas for a while - they need to simmer before we see change. Do your part and insist on answers from people that show The Fear.
Send emails to the Human Resources department of your 3 favorite (ha) corporations. Ask them if they would discriminate against you and cordially offer to provide the necessary medical/legal documents. Make them encounter this situation and become befuddled about the unfamiliar. Ask them how they can accommodate your medical requirements. Tell them that you would never come to work under the influence of any drug, that cannabis is only one component of an alternative therapy recommended by your doctor, and that cannabis is consumed on YOUR time. Be respectful and behave as though nothing is unnatural, no different than asking how they would address your wheelchair needs, or you failing a drug test for having ADD meds prescribed.
Ask Wal-Mart, Ask IBM, Ask McDonalds, Ask Home Depot, Ask Enron