Restricted items as defined by the Royal Mail, with Jamaica being a Commonwealth country probably applies:
Prescription medicines and drugs sent for scientific purposes May only be sent by, or at the specific request of, a qualified medical practitioner, registered dental practitioner, veterinary surgeon, registered nurse or a recognised laboratory or institution.
Medicines classified as non-flammable or non-toxic must be securely closed and placed in a leak-proof container such as a sealed polythene bag (for liquids) or a siftproof container (for solids). Must be tightly packed in strong outer packaging and must be secured or cushioned to prevent any damage. The sender’s name and return address must be clearly visible on the outer packaging.
Medicines classified as flammable, toxic or flammable and toxic are prohibited. Please see www.royalmail.com/internationalprohibitedgoods
