ALBANY — New Yorkers with cancer, AIDS, Parkinson’s disease, or other qualifying conditions will be able to obtain medical marijuana as early as Thursday, 18 months after lawmakers passed what is considered one of the strictest medical cannabis programs in the nation.

The program is off to a slow start: Only 150 physicians have completed the required registration with the state, and only eight of 20 dispensaries expect to open on Thursday. The remaining 12 are expected to open by month’s end.

‘‘Our pharmacists are ready,’’ said Nicholas Vita, CEO of Columbia Care NY, which intends to open its first dispensary this week near Manhattan’s Union Square, followed by other locations in Suffolk, Clinton and Monroe counties. ‘‘Our product is ready. It’s been tested by the state and validated.’’

To receive medical cannabis a person must obtain certification from a physician registered with the program, and apply for an identification card from the state’s Department of Health. The drugs will come in the forms of capsules and oils and tinctures that can be vaporized or used in inhalers.

The state’s caution was intended to address fears that marijuana would be diverted for recreational uses.

Associated Press