Uruguay's parliament gave final approval to the measure in December 2013, making Uruguay the first country in the world to fully legalize cannabis for retail distribution.
The marijuana sold at the pharmacies comes from state-supervised fields.
In all, 16 pharmacies have been authorized to sell marijuana under state controls, barely enough to cover a country of 3.5 million people.
Many pharmacies have been unwilling to become points of sale for the drug, because of concerns about security and doubts that the small market of registered users is worth the trouble.
Nearly 5,000 people have signed up to a national registry to be able to buy marijuana legally.
Officials said about 70% of people who had registered to buy marijuana from pharmacies where men, a lot of them aged between 30 and 44.
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This week Uruguay will officially begin legal sales of marijuana for those 18 and older, over three and a half years after the law legalizing the plant was initially approved by lawmakers.. The new law also allowed up to 45 people to operate grow houses, or "clubs", with up to 99 plants for members' personal use.
Only two companies were authorized to produce marijuana for pharmacies-under military protection, and with no public access.
The price is set at the equivalent of $1.30 per gram.
An "Alfa I" package contains "Alfa I variety cannabis hybrid with Indica predominant". Everyone who entered the list of users will have the right to buy a maximum of 10 grams per week. I have talked to people that have consume marijuana in Uruguay, including my buddy Jorge Cervantes, and they all say that cannabis in Uruguay is of good quality.
Diego Zas shows two bags of legal marijuana he just bought at the Antartida drugstore in downtown Montevideo, Uruguay, Wednesday, July 19, 2017.