Paracetamol Causes Acute Liver Damage

PARACETAMOL (acetaminophen) is an effective painkiller but a risky one. It is the leading cause of acute liver damage in the US.

Now there are two ways it could get a whole lot safer. A US Food and Drug Administration panel wants to slash the recommended dosage and now a safer alternative can be made cheaply for the first time.

When used as directed paracetamol is safe, but it doesn't take much more than the recommended dose to cause permanent, possibly fatal, liver damage.

Among over-the-counter drugs, "it probably has the smallest difference between how much it takes to be effective and how much it takes to cause damage", says Sidney Wolfe of the watchdog group Public Citizen in Washington DC.

Because paracetamol is an ingredient of numerous preparations, from cold medicines to prescription narcotics such as Vicodin, it's easy to double-dose by mistake.

Last month the FDA's advisory panel recommended specifying smaller doses of paracetamol and clearer labelling of medications that contain it. More controversially, the panel recommended removing it entirely from prescription narcotics. The FDA usually follows its panel's recommendations.

A more comprehensive solution may be on the horizon, in the form of drugs such as SCP-1, which is made up of a molecule of paracetamol joined to a saccharin molecule. In early tests in people SCP-1 does not seem to produce the same toxic by-products as paracetamol.

Now Mark Trudell and colleagues at the University of New Orleans, Louisiana, together with the New Orleans company St Charles Pharmaceuticals, which ran the tests, have reported a way to synthesise SCP-1 cheaply and in large quantities (Organic Process Research and Development, DOI: 10.1021/op900113b).