Supporters of the move say allowing cheaper imports will force sky-high U.S. pharmaceutical prices down. Detractors, including the pharmaceutical industry, warn of "unsafe" foreign medications.
The Food and Drug Administration (FDA) does not allow the importation of foreign drugs, also warning of risky foreign pharmaceuticals and counterfeit drugs.
But the supposed safety risks haven't stopped U.S. consumers from importing their prescriptions at a discount anyway.
The Centers for Disease Control (CDC) found that in 2009 25 million Americans didn’t take prescribed medication due to high drug costs.
State officials and foreign drug companies say the imported drugs aren't risky, and that the complaints of U.S. pharmaceutical companies are based in protecting their profits.
"It’s not a safety issue," Maine's Republican Governor Paul LePage said in an interview with the Wall Street Journal. "It’s turf."
Officials found that Portland residents paying cash to import popular prescription drugs including Nexium, Crestor and Advair Diskus from Canada experienced huge savings.
Nexium, the popular "purple pill" heartburn and acid reflux prescription cost just $200.90 for a 90-day supply of 10mg pills through Canadian broker CanaRx.
The city's health insurer, Aetna, negotiated a total cost of $621.08 for the same supply of 10mg Nexium, with $465.81 to be paid by the employer and $155.27 to be paid by the employee.
Under the new law, Maine residents will be able to buy mail-order drugs from licensed retail pharmacies in Canada, Australia, New Zealand and the United Kingdom.
The law, going into effect despite many legal delays, continues to be challenged. Maine pharmacy groups and the Pharmaceutical Research and Manufacturers of America are challenging the Maine law in federal court.
"If Maine can do this, other states will do this," said Laurence Kotlikoff, an economics professor at Boston University. "It could have a big impact on pharmaceutical companies' long-term profits and desire to invent new medications."