The number of people registering to buy newly legalized marijuana in Uruguay jumped by almost 50 percent in the first week of sales, according to official figures released Wednesday.
The small South American country is the first in the world to legalize pot from production to sale.
The drug is sold only to people who have officially registered with a licensed pharmacy, and with a monthly limit of 40 grams.
The Institute for the Regulation and Control of Cannabis (IRCCA) said the number of registered applicants leapt from 4,959 last week to 7,343 this week, a 48 percent increase.
The spike in demand meant that the 16 pharmacies that have enrolled in the groundbreaking scheme have been forced to restock several times since sales began on July 19.
Many pharmacies had been unwilling to participate in the scheme because of concerns about security and doubts that the small market of registered users was worth the trouble.
Only two companies are authorized to produce marijuana for pharmacies -- under military protection, and with no public access.
Walk-in sales at pharmacies are not allowed under the law, and only residents of Uruguay can register to buy pot -- thereby preventing marijuana tourism.
The drug can also be grown by private citizens in conditions monitored by the authorities for compliance in the quantity and quality of the plants.
The system -- the first time ever that a state has put itself in charge of the production and distribution of marijuana -- is designed to undercut lucrative and illegal drugs trafficking.
Pharmacy sales are the last of three phases set out under the 2013 law.
Under the early phases, nearly 7,000 people registered to grow weed at home, and more than 60 smokers' clubs were authorized.
The marijuana is sold in five-gram packets and in two varieties with differing strengths of THC, the psychotropic constituent that gives users their high. It costs $1.30 per gram.