Objectives The objectives of this article are to list the most commonly prescribed Oral Nutritional Supplements in the UK and Ireland and their sugar content; and to raise awareness among the dental profession regarding their uses and potential dental risks involved. Background Many older patients benefit from Oral Nutritional Supplements. Prescribers may not consider dental implications of these. Patients may not think to disclose these medications to their dentist. Materials and Methods A list of commonly prescribed Oral Nutritional Supplements in the UK and Ireland was compiled. Nutritional information was obtained from the manufacturers' website and arranged in order of decreasing sugar content. Potential dental implications are discussed and recommendations made for dental practitioners. Results Pre-formed Oral Nutritional Supplements can contain between 6.6 and 27.2 g of sugar per serving. Powdered Oral Nutritional Supplements, which are to be mixed with 200 ml whole milk, contain between 16.4 and 35.0 g sugar per serving. The "shot"-type Oral Nutritional Supplements contain less sugar, ranging from 0.0 to 4.0 g per serving. Conclusions The sugar content of frequently prescribed Oral Nutritional Supplements can be high. While they are beneficial in assisting the patient to maintain a healthy BMI, they may increase the risk of dental caries. Dental professionals should enquire specifically about Oral Nutritional Supplements during history taking, particularly in groups who are likely to be prescribed such supplements. Consideration should also be given to increasing caries-preventive measures for patients who take these supplements.