Off-label prescribing is common

Reported by Susan Aldridge, PhD, medical journalist

As many as one in five of prescriptions are for an off-label use, even though most of these uses are not backed by scientific evidence.
The US Food and Drug Administration evaluates new drugs, but does not control doctors' prescribing practises. Therefore, your physician can prescribe drugs for any medical purpose he or she thinks fit. A team at Dartmouth Medical School has been looking into how common 'off-label' prescribing - that is, prescribing a drug for other than its licensed indication - actually is.

They surveyed prescriptions issued by around 3,500 physicians on two consecutive workdays during each quarter of 2001. From this data, the researchers selected information on 100 commonly prescribed drugs and 60 additional drugs, categorizing the prescriptions as on or off label. They also checked to see if there was strong scientific evidence for these off-label prescriptions.

They found that 85 per cent of prescriptions were for on-label use or off-label use with strong scientific support. But 21 per cent were for off-label use of which three quarters did not have strong evidence. Cardiac and asthma medications were the ones most likely to be prescribed off-label. Psychiatric and allergy medications were most likely to be prescribed off-label without strong support. Although off-label prescribing can be a good way of turning scientific knowledge into effective clinical practise, the researchers warn that it may put the patient at risk in some situations.

Source
Archives of Internal Medicine 8th May 2006 Volume 166 pages 1021-1026