Counterfeit drugs may contain harmful ingredients or no active ingredient at all
A global treaty to crack down on the deadly trade of fake medicines is urgently needed, say experts.
Currently, there are more sanctions around the use of illegal tobacco than counterfeit drugs.
Writing in the British Medical Journal, experts urge the World Health Organization to set up a framework akin to its one tobacco control to safeguard the public.
WHO says more than one in every 10 drug products in poorer nations are fake.
A third of malaria drugs are counterfeit, research suggests.
In richer countries, medicine safety is better, but substandard and falsified drugs still cause thousands of adverse reactions and some deaths.
Recently, in the US, contaminated drug supplies caused an outbreak of meningitis that has so far killed 16 people.
Amir Attaran and colleagues from the World Federation of Public Health Associations, International Pharmaceutical Federation and the International Council of Nurses, say while governments and drug companies alike deplore unsafe medicines, it is difficult to achieve agreement on action because discussions too often trespass into conflict-prone areas such as pharmaceutical pricing or intellectual property rights.
Although some countries prohibit fake medicines under national law, there is no global treaty which means organised criminals can continue to trade using haven countries where laws are lax or absent.
WHO estimates nearly a third of countries have little or no medicine regulation.
In other contexts, global treaties have helped governments strengthen their laws and cooperate internationally to clamp down on havens - for example, on money laundering.
Similarly, a new protocol under the Framework Convention on Tobacco Control requires tobacco products to be tracked and criminalises illicit trade globally - "oddly making the law tougher on cigarette falsification than on medicine falsification", says Amir Attaran.
"The protocol will now make it a requirement to track and trace tobacco products. Cigarette packets can carry serial numbers so it is possible to track them from beginning to end.
"If this is something you can do for a $5 cigarette packet I do not see why we can't do it for a $3,000 packet of drugs that could save your life.
"In Canada we have seen a fake version of the heart drug Avastin come into the country that contains no active drug, just starch and nail polish remover.
"When you are dealing with a medicine like that if there was a serial number on it you would be able to easily see if it was fake."
WHO says it provides direct country and regional support for strengthening medicines regulation.
And it is up to its 194 member states to decide if a treaty is the way forward.
In 2011, a directive to protect patients from fake medicines was approved by the European Parliament.