title: Low-dose lactose in drugs neither increases breath hydrogen excretion nor causes gastrointestinal symptoms.
abstract: BACKGROUND
  Despite the reported tolerance to a low dose of lactose, many lactose malabsorbers follow a rigorous lactose-free diet also avoiding lactose-containing drugs. Up to now, only a few case reports have described the onset of gastrointestinal symptoms in lactose malabsorbers following the ingestion of these drugs. It has been suggested that capsules/tablets contain no more than 400 mg of lactose.
  
  
  OBJECTIVE
  To evaluate breath H(2) excretion and intolerance symptoms after ingestion of a capsule containing 400 mg of lactose or placebo through a randomized, cross-over, double-blind, controlled study.
  
  
  METHODS
  Seventy-seven lactose maldigesters with intolerance underwent two H2 breath tests with both 400 mg of lactose and 400 mg of placebo. Gastrointestinal symptoms occurring in the 8 h following the ingestion of different substrates were evaluated by a visual-analogue scale.
  
  
  RESULTS
  Ingestion of 400 mg of lactose did not cause a significant difference in breath H2 excretion or in the severity of gastrointestinal symptoms compared to placebo.
  
  
  CONCLUSIONS
  In patients with lactase deficiency, drugs containing 400 mg of lactose or less can be used safely.
authors.affiliation: Institute of Internal Medicine, Catholic University, Rome, Italy. mmontalto@rm.unicatt.it
authors.forename: M
authors.initials: M
authors.lastname: Montalto
authors.forename: A
authors.initials: A
authors.lastname: Gallo
authors.forename: L
authors.initials: L
authors.lastname: Santoro
authors.forename: F
authors.initials: F
authors.lastname: D'Onofrio
authors.forename: V
authors.initials: V
authors.lastname: Curigliano
authors.forename: M
authors.initials: M
authors.lastname: Covino
authors.forename: G
authors.initials: G
authors.lastname: Cammarota
authors.forename: A
authors.initials: A
authors.lastname: Grieco
authors.forename: A
authors.initials: A
authors.lastname: Gasbarrini
authors.forename: G
authors.initials: G
authors.lastname: Gasbarrini
mesh_terms: D015746:Abdominal Pain / Q000209:etiology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001944:Breath Tests / Q000379:methods; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D005767:Gastrointestinal Diseases / Q000209:etiology*; D006801:Humans; D006859:Hydrogen / Q000032:analysis; D007785:Lactose / Q000009:adverse effects*; D007787:Lactose Intolerance / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D013223:Statistics as Topic
chemical_list: D006859:Hydrogen; D007785:Lactose