This article looks at the legal implications of using a Chlorhexidine based product as a medicine, where that product does not have a marketing authorisation under the Human Medicines Regulations 2012, but where it is authorised for use as a biocidal product under the EU Biocides Regulations 528/2012.

In recent guidance on medicinal products the MHRA addressed the issue of Chlorhexidine in medicinal products [1]. This comes against the background of concerns addressed in 2014 about the risks of the biocidal variation being used as a surgical site skin pre-operative skin preparation. That statement highlighted that:

"there are health risks associated with using Chlorhexidine. Using the appropriately authorised product for its specific intended use, in accordance with the manufacturer’s instructions for use, is the best way of minimising harm"[2]

Chlorhexidine used as part of a biocidal disinfectant is subject to the EU Biocides Regulations 528/2012. Where it is part of a medicinal product, such as a pre-operative skin preparation, it will be regulated by the Human Medicines Regulations 2012. An authorisation under the latter regulations will have been given after more stringent quality and safety assurance requirements have been met relating to the manufacture of the product.

A biocidal product is defined in Article 3(1)(a) of the Biocide Regulations as:

"Any substance or mixture, in the form in which it is supplied to the user, consisting of, containing or generating one or more active substances, with the intention of destroying, deterring, rendering harmless, preventing the action of, or otherwise exerting a controlling effect on, any harmful organism by any means other than mere physical or mechanical action"

This is in contrast to the definition of a medicinal product in Regulation 2(1) of the Human Medicines Regulations:

"any substance or combination of substances presented as having properties of preventing or treating disease in human beings".

In effect, a skin preparation agent which is used to reduce the risk of surgical site infection will be classed as a medicinal product, even if the active ingredient involved is also found in certain biocidal products. A disinfectant not intended for direct application to humans will be a biocidal product governed by the Biocide Regulations.

Article 17(1) of the Biocide Regulations stipulates that "biocidal products should neither be made available on the market nor used unless authorised in accordance with this Regulation". Authorisation is obtained in the UK from the Health and Safety Executive. An authorisation has to set out the terms and conditions of the marketing and use of the biocide product and Article 17(3) of the Biocide Regulations specifies that "biocidal products shall be used in compliance with the terms and conditions of the authorisation" given. The use of the word 'shall' in the Regulations makes this a mandatory obligation. The Biocide Regulations only apply to products if they are not regulated as medicines, but this does not mean that a biocidal product which is duly authorised for use under the Biocide Regulations cannot be used as a medicinal product in accordance with the Human Medicine Regulations, ie to prevent or treat disease in human beings. But for the latter to be lawful, the biocidal product must also have a marketing authorisation granted under the Human Medicines Regulations.

In distinguishing between products which might be considered as falling under both sets of regulations, the MHRA's position has been clarified in its recent guidance:

Topical Chlorhexidine antiseptic products that are intended by the manufacturer to be used for a medical purpose, such as the preparation of the skin prior to surgery, will be classified as a medicinal product.

Under Regulation 46(1) of the Human Medicines Regulations a person may not sell or supply, or offer to sell or supply, an unauthorised medical product. Under Regulation 46(5) a person may not procure the sale, supply, manufacture or assembly of a medicinal product where he knows or has reasonable cause to know that the product has been or will be supplied where no marketing authorisation is in place for that product. It is an offence to act in breach of Regulation 46.

The effect of this is that if a healthcare provider purchases a product containing Chlorhexidine for use as a pre-surgical preparation agent, but knows or should know that there is no marketing authorisation issued under the Human Medicines Regulations in place for that product, the procurement officer undertaking the purchase may be committing an offence.

A marketing authorisation is not needed in limited circumstances where an exemption applies, but this arises in circumstances needed to meet the special needs of an individual patient and an unlicensed medicinal product should not be supplied where an equivalent licensed product can meet the special needs of the patient [3]. Detailed conditions must be met for the exemption provisions to engage.

It has long been the case that medicines can be prescribed for a therapeutic purpose even though not licensed specifically for that purpose. Off-license (or 'unauthorised', ie without a marketing authorisation) prescription is addressed in GMC guidance:

“You should usually prescribe licensed medicines in accordance with the terms of their licence. However, you may prescribe unlicensed medicines where, on the basis of an assessment of the individual patient, you conclude, for medical reasons, that it is necessary to do so to meet the specific needs of the patient.

Given the routine nature of the use of pre-operative surgical site sterilisation agents, it is unlikely that either the exception in Human Medicines Regulations, or the GMC guidance would amount to a justification for such use where no marketing authorisation was in place.

A situation may arise whereby a biocidal product containing Chlorhexidine is used for pre-surgical site preparation, but where it had been supplied as a biocide and both seller and buyer had no reason to believe it would be used for a medicinal purpose. In other words, a situation which falls outside the embrace of Regulation 46 of the Human Medicines Regulations 2012, but where a biocidal product is being used as a medicinal product outside the terms of its authorisation from the Health and Safety Executive. In such circumstances the use of the biocide would be in breach of both Article 17(1) and 17(3) of the Biocides Regulations.

The Biocide Regulations are enforced under the Health and Safety at Work Act 1974 (HASWA). In practical terms, this means that a breach of the Biocide Regulations will be a breach of health and safety regulations for the purposes of HASWA. Responsibility for enforcement will fall to the Health and Safety Executive. Under s.33 (1) (c) of HASWA, it is an offence "to contravene any health and safety regulations…..or any requirement or prohibition imposed under any such regulations (including any requirement or prohibition to which he is subject by virtue of the terms of or any condition or restriction attached to any licence, approval, exemption or other authority issued, given or granted under the regulations)".

HASWA provides for both individual and corporate liability, including individual managerial liability in cases where contravention of the regulations has been actively consented to, or has occurred as the result of negligence. Penalties can include an unlimited fine for offences committed after 12th March 2015. For further guidance on the new sentences see our artcile on Substantial increase in health & safety fines.

The MHRA guidance from March 2016 makes the point that a medicinal product containing Chlorhexidine should be manufactured, supplied and procured in accordance with the Human Medicines Regulations 2012 [1]. If it is supplied as a biocidal product but then used for a medicinal purpose in pre-surgical site sterilisation without appropriate marketing authorisation that may be in breach of the Biocide Regulations 2012 as well and constitute an offence.



1. A guide to what is a medicinal product, MHRA March 2016

2. Joint RCS/MHRA statement on use of topical chlorhexidine for skin preparation prior to surgery

3. The Human Medicines Regulations 2012, Regulation 167. See also The supply of unlicensed medicinal products ("specials") MHRA 2014


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