Patients registered in New Jersey’s medical marijuana program are waiting weeks — even months — for appointments to obtain the drug from the only dispensary in the state.

The waits are not likely to end soon. The number of patients continues to grow — 645 people are registered, more than twice the amount the dispensary in Montclair anticipated in its first year. Meanwhile, other dispensaries aren’t expected to open for months as they go through a rigorous process to meet state regulations for medical marijuana centers.

“We always wanted to be a small mom-and-pop medical marijuana dispensary,” said Joseph Stevens, president of the Greenleaf Compassion Center in Montclair, which opened in December. “Now we’re servicing the whole state.”