Development of two stable oral suspensions of levodopa-carbidopa for children with amblyopia

J Pediatr Ophthalmol Strabismus. Nov-Dec 2000;37(6):333-7.

Abstract

Purpose: To develop stable liquid dosage forms of levodopa-carbidopa for use in children with amblyopia.

Methods: Levodopa (100 mg) and carbidopa (25 mg) tablets were used to prepare the suspensions at 5 and 1.25 mg/mL, respectively. For each suspension, five bottles were stored at 25 degrees C and five at 4 degrees C. Three samples were taken from each bottle at 0, 7, 14, 28, 42, 56, 70, and 91 days (n=15). Levodopa-carbidopa concentrations for each sample were measured in duplicate by validated and stability-indicating high-performance liquid chromatographic method.

Results: The mean concentrations of levodopa-carbidopa in Ora Plus/Ora Sweet suspensions were 96% and 92% of the initial concentrations for 28 days at 25 degrees C, and 94% and 93% for 42 days at 4 degrees C. In the suspension containing ascorbic acid, the mean concentrations of levodopa-carbidopa were above 93% and 92% for 14 days at 25 degrees C, and 93% and 92% for 28 days at 4 degrees C. This liquid formulation was administered to 15 children (mean age: 5.6+/-1.4 years) with amblyopia. The number and type of adverse effects were similar in the levo-dopa-carbidopa versus placebo group.

Conclusion: Levodopa-carbidopa in extemporaneous suspensions prepared in Ora Plus and Ora Sweet were stable for 28 days when stored at 25 degrees C and for 42 days at 4 degrees C. Our data suggest our liquid formulation may be used safely in children with amblyopia.

MeSH terms

  • Administration, Oral
  • Amblyopia / drug therapy*
  • Carbidopa / chemistry
  • Carbidopa / therapeutic use*
  • Chemistry, Pharmaceutical
  • Child
  • Child, Preschool
  • Chromatography, High Pressure Liquid
  • Dopamine Agents / chemistry
  • Dopamine Agents / therapeutic use*
  • Drug Stability
  • Drug Storage
  • Drug Therapy, Combination
  • Female
  • Humans
  • Levodopa / chemistry
  • Levodopa / therapeutic use*
  • Male
  • Safety
  • Suspensions

Substances

  • Dopamine Agents
  • Suspensions
  • Levodopa
  • Carbidopa