Mention of drug addiction typically conjures up images of strung-out users of heroin or crack cocaine. But a growing number of Britons are dependent on legal drugs, prescribed by their doctors, with a grip as unforgiving as that of their illegal counterparts. It is a problem that cannot keep being ignored.

Despite the efforts of campaigners, the blight of addiction to prescription medicines – in particular opiate-based painkillers and benzodiazepine tranquillisers – remains low on the agenda and largely unexamined. What glimmers of statistical light there are, are increasingly disturbing. Opiate painkillers are being dispensed at five times the rate they were 20 years ago, for example, while deaths involving codeine doubled between 2005 and 2009 alone.

In part, the problem reflects patient demand. There is a growing battery of drugs to combat anxiety and chronic pain, and sufferers are unsurprisingly keen to make use of them. But there is a balance to be struck. Patients may not be aware of the potency of their medication until it is too late, while GPs too often boost doses far above recommended levels if patients' complaints continue.

The real worry is the unknown scale of the problem. While estimates suggest around 1.5 million people could be hooked on their medicine, the issue receives so little attention that there may be many more who are unaware they have a problem, and there is little support for those that do.

The piecemeal approach from the Department of Health so far is insufficient. Addiction to prescription drugs needs a coordinated response: clearer guidelines for doctors, closer monitoring of patients, tighter controls on drug marketing, more help for addicts. But the crucial first step, as with addiction, is to face up to the fact there is a problem.