All lactase preparations are not the same: results of a prospective, randomized, placebo-controlled trial

Am J Gastroenterol. 1994 Apr;89(4):566-70.


Objective: To compare the efficacy of three commercially available oral lactase preparations in adults with lactose intolerance.

Methods: Design--Prospective, randomized, placebo-controlled trial. Setting--Outpatient study in a General Clinical Research Center. Subjects--Ten lactose-intolerant healthy volunteers were challenged with ice cream containing 18 g of lactose. Lactase or placebo was given immediately prior to challenge. Measurements--Symptoms and breath hydrogen excretion were recorded for 3 h following lactose challenge.

Results: The three products differed in their abilities to influence symptoms and breath hydrogen excretion. Only Lactaid reduced the breath hydrogen excretion with lactose (mean peak, area under the curve and cumulative breath hydrogen excretion) (p < 0.05). Lactrase and Dairy Ease influenced symptoms: Lactrase reduced pain, bloating and total symptomatic scores (p < 0.05), whereas Dairy Ease only reduced pain (p < 0.05). Lactaid administration did not reduce symptoms.

Conclusion: In lactose-intolerant subjects, the available lactase preparations differ in their ability to improve both breath hydrogen excretion and symptoms. Lactrase may be the product of choice for achieving symptomatic improvement.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Breath Tests
  • Chemistry, Pharmaceutical
  • Female
  • Humans
  • Hydrogen / analysis
  • Ice Cream
  • Lactose Intolerance / drug therapy*
  • Male
  • Prospective Studies
  • Single-Blind Method
  • beta-Galactosidase / administration & dosage
  • beta-Galactosidase / therapeutic use*


  • Hydrogen
  • beta-Galactosidase