{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T14:00:56Z","timestamp":1789999256707,"version":"4.0.1"},"reference-count":47,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T00:00:00Z","timestamp":1789948800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Vitaflo International"},{"name":"Nutrinovo"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Background\/Objectives: Timely access to protein substitutes and special low-protein foods (SLPFs) is essential for effective dietary management of phenylketonuria (PKU). As key healthcare professionals responsible for coordinating and delivering nutritional therapy, metabolic dietitians are directly involved in managing prescription-related issues that may arise within the access pathway. This study aimed to identify the main prescription-related barriers experienced by metabolic dietitians in the UK and to explore their implications for patient care, clinical workload, and the delivery of specialist PKU services. Methods: A structured questionnaire was distributed by the National Society for Phenylketonuria to dietitians involved in the care for individuals with PKU in the UK. Anonymised responses were analysed descriptively to identify the types, frequency, and impact of prescription-related issues. Results: A total of 448 responses were received from metabolic dietitians across the UK reporting prescription-related problems affecting dietary products. Most reported incidents involved children (306\/446; 68.6%). Among responses specifying the affected product category (n = 443), SLPFs accounted for most reported problems (261\/443; 58.9%), followed by protein substitutes (120\/443; 27.1%) and finally combined protein substitute and SLPF issues (62\/443; 14.0%). Qualitative analysis identified barriers across all stages of the prescribing pathway, with issues primarily relating to GP prescribing processes, home delivery and supply, pharmacy services, and broader administrative and system-related factors. These disruptions affected continuity of dietary management and metabolic care, with reported consequences including reduced access to prescribed dietary products, difficulties maintaining dietary adherence, increased patient and family burden, anxiety and frustration, and a substantial hidden workload for metabolic dietetic services. Conclusions: Prescription-related problems represented a significant barrier to timely access to essential medical foods for individuals with PKU in the UK. The findings highlight challenges across the prescribing and supply pathway that compromise access to both protein substitutes and SLPFs, impose additional burdens on patients and families, and increase workload for specialist metabolic dietetic services. Addressing these system-level barriers, alongside strengthening communication, coordination, and prescribing processes across stakeholders, may improve continuity of dietary treatment and enable more efficient delivery of specialist metabolic care.<\/jats:p>","DOI":"10.3390\/nu18183092","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T12:50:03Z","timestamp":1789995003000},"page":"3092","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Impact of Prescription Barriers to Special Low Protein Foods and Protein Substitutes on PKU Care: Findings from a National Survey of Metabolic Dietitians"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4859-5288","authenticated-orcid":false,"given":"Martina","family":"Tosi","sequence":"first","affiliation":[{"name":"Department of Dietetics, Birmingham Women\u2019s and Children\u2019s Hospital, Birmingham B4 6NH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1041-2116","authenticated-orcid":false,"given":"Suzanne","family":"Ford","sequence":"additional","affiliation":[{"name":"National Society for Phenylketonuria (NSPKU), Sheffield S12 9ET, UK"},{"name":"Department of Nutrition & Dietetics, Bristol NHS Foundation Trust, Bristol Royal Infirmary, Bristol BS2 8HW, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anne","family":"Grimsley","sequence":"additional","affiliation":[{"name":"Royal Belfast Hospital for Sick Children, 274 Grosvenor Rd, Belfast BT12 6BA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah","family":"Bailey","sequence":"additional","affiliation":[{"name":"All Wales Inherited Metabolic Disease Service, University Hospital of Wales, Heath Park Way, Cardiff CF14 4XW, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2896-3509","authenticated-orcid":false,"given":"Anita","family":"MacDonald","sequence":"additional","affiliation":[{"name":"Department of Dietetics, Birmingham Women\u2019s and Children\u2019s Hospital, Birmingham B4 6NH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"109125","DOI":"10.1016\/j.ymgme.2025.109125","article-title":"European Guidelines on Diagnosis and Treatment of Phenylketonuria: First Revision","volume":"145","author":"MacDonald","year":"2025","journal-title":"Mol. Genet. Metab."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1186\/s13023-020-01391-y","article-title":"PKU Dietary Handbook to Accompany PKU Guidelines","volume":"15","author":"MacDonald","year":"2020","journal-title":"Orphanet J. Rare Dis."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"103591","DOI":"10.1016\/j.clnesp.2026.103591","article-title":"Nutritional and Metabolic Management of Phenylketonuria: Integrating Dietary Strategies, Medical Nutrition Therapy, and Emerging Treatments","volume":"75","author":"Coban","year":"2026","journal-title":"Clin. Nutr. ESPEN"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"162","DOI":"10.1186\/s13023-017-0685-2","article-title":"The Complete European Guidelines on Phenylketonuria: Diagnosis and Treatment","volume":"12","author":"MacDonald","year":"2017","journal-title":"Orphanet J. Rare Dis."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Daly, A., Evans, S., Pinto, A., Ashmore, C., and MacDonald, A. (2021). Protein Substitutes in PKU; Their Historical Evolution. Nutrients, 13.","DOI":"10.3390\/nu13020484"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"702","DOI":"10.1016\/j.clnu.2020.11.003","article-title":"Dietary Protein and Protein Substitute Requirements in Adults with Phenylketonuria: A Review of the Clinical Guidelines","volume":"40","author":"Firman","year":"2021","journal-title":"Clin. Nutr."},{"key":"ref_7","first-page":"100527","article-title":"Prescribing Issues Experienced by People Living with Phenylketonuria in the UK","volume":"21","author":"Ford","year":"2019","journal-title":"Mol. Genet. Metab. Rep."},{"key":"ref_8","first-page":"100466","article-title":"Home Delivery Service of Low Protein Foods in Inherited Metabolic Disorders: Does It Help?","volume":"19","author":"MacDonald","year":"2019","journal-title":"Mol. Genet. Metab. Rep."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Poloni, S., Pesce, L.d.A., Kanufre, V.d.C., Farret, L.R., Pugliese, C., Silva, J.A.d.O., Poubel, M., Leite, M.E.d.Q., Oliveira, R.B.d., and SBTEIM Nutrition Department (2026). A National Overview of Nutritional Care in Diet-Treated Inborn Errors of Metabolism in Brazil. Int. J. Environ. Res. Public Health, 23.","DOI":"10.3390\/ijerph23060807"},{"key":"ref_10","first-page":"e918","article-title":"Access to life-saving foods for special medical purposes for patients with inherited metabolic disorders: A national survey of Italian dietitians","volume":"2","author":"Gentilucci","year":"2025","journal-title":"J. Innate Metab."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"428","DOI":"10.12968\/jprp.2025.0079","article-title":"Exploring Delays in Nutritional Product Access for Children and Young People","volume":"7","author":"Owen","year":"2025","journal-title":"J. Prescr. Pract."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Evans, S., Arbuckle, C., Ashmore, C., Bailey, S., Blaauw, G., Chaudhry, W., Dale, C., Daly, A., Downey, B., and Dundas, J. (2025). UK Patient Access to Low-Protein Prescription Foods in Phenylketonuria (PKU): An Uneasy Path. Nutrients, 17.","DOI":"10.3390\/nu17030392"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"375","DOI":"10.1111\/j.1365-277X.2006.00717.x","article-title":"Home Delivery of Dietary Products in Inherited Metabolic Disorders Reduces Prescription and Dispensing Errors","volume":"19","author":"MacDonald","year":"2006","journal-title":"J. Hum. Nutr. Diet."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"390","DOI":"10.1016\/j.ymgme.2011.12.004","article-title":"Diet in Phenylketonuria: A Snapshot of Special Dietary Costs and Reimbursement Systems in 10 International Centers","volume":"105","author":"Dokoupil","year":"2012","journal-title":"Mol. Genet. Metab."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"2249","DOI":"10.2147\/PPA.S481857","article-title":"A Qualitative Investigation into the Determinants of Unfulfilled Needs in Caregivers of Patients with Phenylketonuria","volume":"18","author":"Zheng","year":"2024","journal-title":"Patient Prefer. Adherence"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"113300","DOI":"10.1016\/j.nut.2026.113300","article-title":"Living with Phenylketonuria in Adulthood","volume":"150","author":"Haitjema","year":"2026","journal-title":"Nutrition"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Kalkan, D., Y\u0131ld\u0131z, Y., Karanfil, Y., Korkusuz, F., Dursun, A., Sivri, S., and G\u00f6kmen \u00d6zel, H. (2026). Nutritional Status and Physical Activity Levels in Adult Patients with Phenylketonuria. Nutrients, 18.","DOI":"10.3390\/nu18111804"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"e050283","DOI":"10.1136\/bmjopen-2021-050283","article-title":"Exploration of Prescribing Error Reporting across Primary Care: A Qualitative Study","volume":"12","author":"Hall","year":"2022","journal-title":"BMJ Open"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"831","DOI":"10.1001\/jama.297.8.831","article-title":"Deficits in Communication and Information Transfer between Hospital-Based and Primary Care Physicians: Implications for Patient Safety and Continuity of Care","volume":"297","author":"Kripalani","year":"2007","journal-title":"JAMA"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1111\/jhn.12199","article-title":"A Questionnaire Survey on the Usage of Low Protein Staple Foods by People with Phenylketonuria in Scotland","volume":"27","author":"Cochrane","year":"2014","journal-title":"J. Hum. Nutr. Diet."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"417","DOI":"10.7326\/0003-4819-157-6-201209180-00006","article-title":"Improving Patient Handovers from Hospital to Primary Care: A Systematic Review","volume":"157","author":"Hesselink","year":"2012","journal-title":"Ann. Intern. Med."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"418","DOI":"10.1093\/intqhc\/mzv063","article-title":"Resilient Health Care: Turning Patient Safety on Its Head","volume":"27","author":"Braithwaite","year":"2015","journal-title":"Int. J. Qual. Health Care"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"56","DOI":"10.1016\/j.appet.2013.04.016","article-title":"Intentional and Inadvertent Non-Adherence in Adult Coeliac Disease. A Cross-Sectional Survey","volume":"68","author":"Hall","year":"2013","journal-title":"Appetite"},{"key":"ref_24","unstructured":"NHS England (2026, August 03). Prescribing Gluten-Free Foods in Primary Care: Guidance for Clinical Commissioning Groups\u2013Frequently Asked Questions. Available online: https:\/\/www.england.nhs.uk\/medicines-2\/medicines-optimisation\/prescribing-gluten-free-foods-in-primary-care-guidance-for-ccgs-faqs\/."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Sha\u2019aban, A., Mazzaschi, F., Doe, E., Ingram, B.-J., Jones, A., Williams, E., O\u2019Sullivan, H., Evans, A., Edwards, A., and Joseph-Williams, N. (2025). Patients\u2019 Views on a Subsidy Card Model for Gluten-Free Food Access: A Qualitative Study. BMC Health Serv. Res., 25.","DOI":"10.1186\/s12913-025-13582-z"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Sugavanam, T., Crocker, H., Violato, M., and Peters, M. (2024). The Financial Impact on People with Coeliac Disease of Withdrawing Gluten-Free Food from Prescriptions in England: Findings from a Cross-Sectional Survey. BMC Health Serv. Res., 24.","DOI":"10.1186\/s12913-024-10600-4"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"e021312","DOI":"10.1136\/bmjopen-2017-021312","article-title":"Trends, Geographical Variation and Factors Associated with Prescribing of Gluten-Free Foods in English Primary Care: A Cross-Sectional Study","volume":"8","author":"Walker","year":"2018","journal-title":"BMJ Open"},{"key":"ref_28","unstructured":"(2026, August 03). Overview|Nutrition Support for Adults: Oral Nutrition Support, Enteral Tube Feeding and Parenteral Nutrition|Guidance|NICE. Available online: https:\/\/www.nice.org.uk\/guidance\/cg32\/resources\/nutrition-support-for-adults-oral-nutrition-support-enteral-tube-feeding-and-parenteral-nutrition-pdf-975383198917."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"298","DOI":"10.1111\/jhn.12016","article-title":"Extended Roles and the Dietitian: Community Adult Enteral Tube Care","volume":"26","author":"Stanley","year":"2013","journal-title":"J. Hum. Nutr. Diet."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"418","DOI":"10.1002\/ncp.70101","article-title":"Interdisciplinary Education for the Clinician and Consumer to Enhance the Home Enteral Nutrition Experience: A Narrative Review","volume":"41","author":"Lord","year":"2026","journal-title":"Nutr. Clin. Pract."},{"key":"ref_31","first-page":"201","article-title":"Adequacy of Financing and Prescription of Home Enteral Nutrition. Are Things Being Done Right?","volume":"42","year":"2025","journal-title":"Nutr. Hosp."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1016\/j.clnu.2019.04.022","article-title":"ESPEN Guideline on Home Enteral Nutrition","volume":"39","author":"Bischoff","year":"2020","journal-title":"Clin. Nutr."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"537","DOI":"10.1111\/j.1365-277X.2004.00569.x","article-title":"Home Enteral Feeding Audit","volume":"17","author":"Evans","year":"2004","journal-title":"J. Hum. Nutr. Diet."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Wood, G., Evans, S., Pointon-Bell, K., Rocha, J.C., and MacDonald, A. (2020). Special Low Protein Foods in the UK: An Examination of Their Macronutrient Composition in Comparison to Regular Foods. Nutrients, 12.","DOI":"10.3390\/nu12061893"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Wood, G., Pinto, A., Evans, S., Daly, A., Adams, S., Costelloe, S., Gribben, J., Ellerton, C., Emm, A., and Firman, S. (2021). Special Low Protein Foods Prescribed in England for PKU Patients: An Analysis of Prescribing Patterns and Cost. Nutrients, 13.","DOI":"10.3390\/nu13113977"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1186\/s13023-019-1153-y","article-title":"Clinical Burden of Illness in Patients with Phenylketonuria (PKU) and Associated Comorbidities\u2014A Retrospective Study of German Health Insurance Claims Data","volume":"14","author":"Trefz","year":"2019","journal-title":"Orphanet J. Rare Dis."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"S\u0142omi\u0144ska, D., Ka\u0142u\u017cny, \u0141., and Walkowiak, D. (2026). Invisible but Central: Family Caregiving as the Hidden Infrastructure of Pediatric PKU-an Integrative Review. Syst. Rev.","DOI":"10.1186\/s13643-026-03267-x"},{"key":"ref_38","first-page":"782","article-title":"Factors Affecting the Success of Follow-up and Treatment of Adults with Phenylketonuria Diagnosed by Newborn Screening","volume":"39","author":"Karaca","year":"2026","journal-title":"J. Pediatr. Endocrinol. Metab."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1007\/s00431-026-06933-3","article-title":"Impact of Depression on Quality of Life in PKU Children","volume":"185","author":"Abuelela","year":"2026","journal-title":"Eur. J. Pediatr."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1059","DOI":"10.2147\/PPA.S512719","article-title":"Phenylketonuria as an Adherence Disease","volume":"19","author":"Reach","year":"2025","journal-title":"Patient Prefer. Adherence"},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Yagudina, R., Kulikov, A., Serpik, V., Protsenko, M., and Kopeyka, K. (2024). Factors Affecting Adherence to a Low Phenylalanine Diet in Patients with Phenylketonuria: A Systematic Review. Nutrients, 16.","DOI":"10.3390\/nu16183119"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"753","DOI":"10.7326\/M16-0961","article-title":"Allocation of Physician Time in Ambulatory Practice: A Time and Motion Study in 4 Specialties","volume":"165","author":"Sinsky","year":"2016","journal-title":"Ann. Intern. Med."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"836","DOI":"10.1016\/j.mayocp.2016.05.007","article-title":"Relationship Between Clerical Burden and Characteristics of the Electronic Environment with Physician Burnout and Professional Satisfaction","volume":"91","author":"Shanafelt","year":"2016","journal-title":"Mayo Clin. Proc."},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Graham-Clarke, E., Rushton, A., Noblet, T., and Marriott, J. (2019). Non-Medical Prescribing in the United Kingdom National Health Service: A Systematic Policy Review. PLoS ONE, 14.","DOI":"10.1101\/582718"},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Graham-Clarke, E., Rushton, A., Noblet, T., and Marriott, J. (2018). Facilitators and Barriers to Non-Medical Prescribing\u2013A Systematic Review and Thematic Synthesis. PLoS ONE, 13.","DOI":"10.1371\/journal.pone.0196471"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1111\/jhn.13231","article-title":"The Affordability and Obtainability of Gluten-Free Foods for Adults with Coeliac Disease Following Their Withdrawal on Prescription in England: A Qualitative Study","volume":"37","author":"Crocker","year":"2024","journal-title":"J. Hum. Nutr. Diet."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"453","DOI":"10.1111\/jhn.12728","article-title":"Withdrawing Gluten-Free Food from Prescriptions in England: A Mixed-Methods Study to Examine the Impact of Policy Changes on Quality of Life","volume":"33","author":"Peters","year":"2020","journal-title":"J. Hum. Nutr. Diet."}],"container-title":["Nutrients"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-6643\/18\/18\/3092\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T13:04:04Z","timestamp":1789995844000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-6643\/18\/18\/3092"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,21]]},"references-count":47,"journal-issue":{"issue":"18","published-online":{"date-parts":[[2026,9]]}},"alternative-id":["nu18183092"],"URL":"https:\/\/doi.org\/10.3390\/nu18183092","relation":{},"ISSN":["2072-6643"],"issn-type":[{"value":"2072-6643","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,21]]}}}