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Safe prescribing in the dental setting

28 July 2020

Dr Joe Ingham, dentolegal consultant at Dental Protection, looks at a case that highlights the vital link between dental treatment and a patient’s medical history


Dentists are conferred prescribing rights for a variety of drugs. This privilege is acquired on completion of the dental degree and should never be abused or taken for granted. Keeping abreast of developments in relation to the legal and therapeutic aspects of prescribing promotes patient care and safety in addition to reducing the risk of an untoward incident.

Regular updating of the patient’s medical history is mandatory. It is essential that dental practitioners have an understanding of any medications that their patients take, prescribed or otherwise. It is particularly important to be aware of any side-effects of drugs and how they can manifest in the oral environment.


Lawrence was a long-standing patient of the practice and over the last 25 years had seen various dentists come and go. He had developed glossitis, ulceration of the mucosa and painful angular cheilitis. Lawrence was approaching his 70th birthday and, even by his own admission, was overweight and unfit. His medical history revealed that he had had a problem with his prostate which was now thankfully resolved and was taking medication for high blood pressure.

It became apparent that his oral problems had been present for several months. He had consulted his general medical practitioner who had prescribed a course of antibiotics which had no beneficial effect. His dentist realised that the problem was unlikely to be caused by a bacterial infection and considered that his medical colleague had prescribed an inappropriate medication. His dentist subsequently prescribed him an antifungal medication and booked Lawrence in for a review appointment two weeks later. At the review appointment the dentist fully expected Lawrence to report that his symptoms had resolved. Alas this was not the case.

At this point, the dentist asked Lawrence if he was taking any other medication. He revealed that since his diagnosis of type 2 diabetes he had been prescribed metformin. His medical history form had not been updated and Lawrence thought it unimportant and of no relevance to his dental treatment. On researching the possible side-effects of metformin his dentist was both shocked and surprised to learn that it can cause vitamin B12 deficiency. This may present as glossitis, oral ulceration and angular cheilitis. Further questioning of Lawrence revealed the onset of the symptoms started shortly after commencing the metformin medication.

A failure to have an up-to-date medical history recorded, as well as having an appreciation of the side-effects of drugs, had led to a prolonging of the patient’s symptoms. Additionally, he had been inappropriately prescribed two courses of medication.