What is the typical color of lactulose?

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The Color of Lactulose

Lactulose solution is typically clear, colorless to pale brownish-yellow in appearance. 1

Physical Characteristics of Lactulose

  • Lactulose is available as a viscous, unflavored solution that ranges from clear and colorless to pale brownish-yellow in color 1
  • The FDA-approved lactulose solution contains 667 mg lactulose/mL (10 g/15 mL) 1
  • Under recommended storage conditions (15° to 30°C or 59° to 86°F), a normal darkening of color may occur, which is characteristic of sugar solutions but does not affect its therapeutic action 1

Storage Considerations Affecting Color

  • Prolonged exposure to temperatures above 86°F (30°C) or direct light may cause extreme darkening and turbidity of the solution, which may be pharmaceutically objectionable 1
  • Freezing temperatures may cause the solution to change to a semi-solid state that is too viscous to pour, though normal viscosity returns upon warming to room temperature 1
  • Proper storage in a tight, light-resistant container as defined by USP standards is recommended to maintain the solution's appearance and efficacy 1

Pharmaceutical Form and Composition

  • Lactulose is a synthetic disaccharide (β-galactosido-fructose) that is not digested in the small intestine 2
  • It exerts an osmotic laxative effect in the colon to promote peristalsis 2
  • Lactulose is supplied in various bottle sizes including 8 fl oz (237 mL), 16 fl oz (473 mL), and 32 fl oz (946 mL) 1

Clinical Context

  • Lactulose is FDA-approved for the treatment of constipation at a dose of 10-20 g (15-30 mL or 1-2 packets) daily 2
  • The dose may be increased to 40 g (60 mL or 2-4 packets) daily if needed 2
  • Besides constipation, lactulose is also used in the treatment of hepatic encephalopathy 3
  • When fermented by gastrointestinal bacteria, lactulose produces short chain fatty acids that lower colonic pH 3

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Lactulose enemas in the treatment of hepatic encephalopathy. Do we help or harm?

Revista espanola de enfermedades digestivas, 2017

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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