Design of mobile and website health application devices for drug tolerability in hereditary fructose intolerance.

BACKGROUND: Hereditary fructose intolerance (HFI) is a rare metabolic disease caused by aldolase B deficiency. The aim of our study was to analyse excipient tolerability in patients with HFI and other related diseases and to design mobile and website health applications to facilitate the search for drugs according to their tolerance. RESULTS: A total of 555 excipients listed in the Spanish Medicines Agency database (July 2023) were classified as suitable for HFI patients, suitable with considerations ((glucose and glucose syrup, intravenous sucrose, oral mannitol, polydextrose, gums and carrageenans, ethanol, sulfite caramel and vanilla), not recommended (intravenous mannitol) and contraindicated (fructose, oral sucrose, invert sugar, sorbitol, maltitol, lactitol, isomaltitol, fruit syrups, honey, sucrose esters and sorbitol esters). Glucose and glucose syrup were classified as suitable with considerations due to its possible fructose content and their potential endogenous fructose production. For other related intolerances, wheat starch was contraindicated and oatmeal was not recommended in celiac disease; oral lactose and lactose-based coprocessed excipient (Cellactose®) were not recommended in lactose intolerance; and glucose, invert sugar and oral sucrose were not recommended in diabetes mellitus. The applications were named IntoMed®. Results are listed in order of tolerability (suitable drugs appear first and contraindicated drugs at the end), and they are accompanied by a note detailing their classified excipients. If a drug contains excipients within different categories, the overall classification will be the most restrictive. The apps are also able to classify substances with the same criteria if they act as active ingredients. The tools exhibited good usability (82.07 ± 13.46 points on the System Usability Scale [range: 0-100]) on a sample of HFI patients, their families and health care professionals. CONCLUSIONS: IntoMed® is a tool for finding information about the tolerability of drugs according to excipients for patients with HFI and other related intolerances, with good usability. It is a fast and reliable system that covers the current excipient legislation and expands on it with other specific information: HFI patients should be alert for excipients such as mannitol (especially in intravenous drugs), fruit syrups, honey, sulfite caramel or vanilla. Glucose might contain or produce fructose, and special precaution is needed because of potential errors in their composition.

Reply letter to the editor concerning the article 'Safety of Sars-Cov-2 vaccines administration for adult patients with hereditary fructose intolerance'.

According to the current European medicines legislation, on the labeling is mandatory a warning contraindicating for hereditary fructose intolerance (HFI) patients medicines with oral or parenteral fructose and sorbitol, and oral sucrose, invert sugar, isomaltitol, lactitol and maltitol, but parenteral sucrose is not mentioned. Intravenous administration of sucrose does not increase blood glucose concentrations, because sucrose is poorly oxidized to CO2 and mainly excreted in the urine as a disaccharide; absence of enzimatic activity outside the gut explains why there is not a warning for parenteral sucrose presentations. For this reason, parenteral drugs with sucrose are allowed in HFI patients. Nevertheless, due to interindividual variability and the fact that not all parenterally administered sucrose is recovered in urine, HFI patients need to be closely monitored after parenteral administration of sucrose-containing drugs, especially when the amount exceeds the maximum permissible thresholds.