Leading independent specialists with an interest in vitamin D have called on NICE to make clear the importance of regulated vitamin D products licensed by the MHRA (ie either prescription only medicines (POMs), pharmacy medicines (P) or general sales list (GSL) in its forthcoming public health guideline 'Vitamin D: implementation of existing guidance to prevent deficiency'1.

They fear that unless the guideline makes clear that only licensed vitamin D products should be recommended, prescribed and dispensed, the large and vulnerable group whom the UK CMOs stipulate should be given vitamin D to prevent deficiency2 could be at risk of receiving either a sub-therapeutic or an excessive dose.

Vitamin D, a sterol hormone, is essential for skeletal growth and bone health. Vitamin D deficiency is a serious and increasing UK public health priority, with the latest data from the National Diet & Nutrition Survey show that around 20% of adults in the UK are deficient3. One of the clinical consequences of Vitamin D deficiency in adults is osteomalacia4. In children, deficiency can result in rickets, and there is evidence to show that this condition is re-emerging in the UK5.

Dr Michael Stone, Director of Bone Research, University Hospital, Llandough said: "NICE has a duty to ensure that prescribers and dispensing pharmacists are aware that licenced vitamin D products are available, safe and cost effective. There is no justification for unlicensed products purporting to be medicines to be available on prescription and we call on NICE to accept our recommendation in its final guideline due out in the Autumn".

The Medicines and Healthcare Products Regulatory Agency6, the General Medical Council7 and the Royal Pharmaceutical Society8 all clearly state that where there is an available licensed medicine, it should be prescribed and dispensed in preference to an unlicensed product purporting to be a medicine, such as a food supplement. Not doing so raises potential medico-legal issues for the prescriber and the dispensing pharmacist.

Yet Prescription Cost Analysis data9 shows that the exponential increase in the use of vitamin D products on the NHS in recent years, has been driven by the dispensing of unlicensed products purporting to be medicines. Data comparing similarly formulated preparations reveals, that, in general, licensed preparations are almost 50% less expensive per 1,000 international units supplied10.

Dr Sally Hope, previously a GP Principal for 26 years, now Clinical Assistant in metabolic bone in Oxford said: "I am concerned that the current draft guideline does not acknowledge the difference between medicines licensed by the MHRA and products purporting to be medicines. In its current form, this guideline has the potential to cause confusion among prescribers, dispensing pharmacists and the general public. There are risks for prescribers if prescriptions are filled using unlicensed products."

Dr Brian Curwain, independent pharmaceutical consultant commented: "Food supplements are variable in their composition, both in terms of the active ingredient and potentially allergenic excipients, colours etc, that they contain. It is important that NICE acknowledges that there are greater risks to health professionals in terms of their legal responsibility in supplying food supplements than in licensed vitamin D medicines."

The public consultation on the draft guidance closes on 24 June and final guidance is expected in November 2014.