title: Risk of vitamin A toxicity from candy-like chewable vitamin supplements for children.
abstract: Numerous vitamin supplements are available over-the-counter to the general public. Some such supplements are available as candy-like chewable preparations to encourage consumption by children. We report 3 cases of overdose of such preparations. Each patient had taken an estimated 200,000 to 300,000 IU of vitamin A. Their circulating vitamin A (retinol and retinyl palmitate) concentrations were monitored over a 6-month period. There were no clinical or biochemical complications noted. However, there were marked increases in both retinol and retinyl palmitate concentrations above age-related reference ranges. In particular, it took 1 to 3 weeks for the serum retinol concentrations to peak and many months for them to normalize. Parents should be warned about the dangers of excessive vitamin consumption. Clinicians should be aware of the late peak in serum retinol concentrations, which may lead to late complications of vitamin A overdose.
authors.affiliation: Department of Pediatrics, Prince of Wales Hospital, Chinese University of Hong Kong, Sha Tin, New Territories, Hong Kong. hshslam@cuhk.edu.hk
authors.forename: Hugh Simon
authors.initials: HS
authors.lastname: Lam
authors.forename: Chung Mo
authors.initials: CM
authors.lastname: Chow
authors.forename: Wing Tat
authors.initials: WT
authors.lastname: Poon
authors.forename: Chi Kong
authors.initials: CK
authors.lastname: Lai
authors.forename: Kwan Chee Allen
authors.initials: KC
authors.lastname: Chan
authors.forename: Wai Lan
authors.initials: WL
authors.lastname: Yeung
authors.forename: Joannie
authors.initials: J
authors.lastname: Hui
authors.forename: Albert Yan Wo
authors.initials: AY
authors.lastname: Chan
authors.forename: Pak Cheung
authors.initials: PC
authors.lastname: Ng
mesh_terms: D001711:Biotransformation; D002182:Candy; D002675:Child, Preschool; D019587:Dietary Supplements / Q000009:adverse effects*; D004224:Diterpenes; D062787:Drug Overdose; D004872:Ergocalciferols / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics; D005500:Follow-Up Studies; D006723:Hong Kong; D006801:Humans; D006986:Hypervitaminosis A / Q000209:etiology*; D008297:Male; D000084562:Retinyl Esters; D012306:Risk; D013607:Tablets; D014801:Vitamin A / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics
chemical_list: D004224:Diterpenes; D004872:Ergocalciferols; D000084562:Retinyl Esters; D013607:Tablets; D014801:Vitamin A; C014794:retinol palmitate