Hi Markis
You can get your question answered by reading The Dangerous Drug Act Fact Sheet Booklet, found on the Jamaica Ministry of Justice website -- https://moj.gov.jm/
In case you don't want to download and read the whole thing, the relevant information, found on page 8, is as follows.
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"Visitors to Jamaica Who Are Users of Medical Marijuana
28. Persons who do not ordinarily reside in Jamaica (for example, tourists or visiting Jamaicans who live overseas) may apply for a permit to allow them to lawfully purchase and possess up to 2 ounces of ganja at a time, for medical or therapeutic purposes.
29. To obtain this permit, visitors will need to produce evidence that their use of ganja has been recommended or prescribed by a licensed medical practitioner in the country where they live. Alternatively, they can sign a voluntary declaration to confirm this. The permit is issued by Jamaica’s Ministry of Health, and a fee is payable."
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