In vitro dissolution characteristics of patent, generic and similar brands of naproxen in various dissolution media

  • María F. Rocha-Alcaraz
  • Erandis D. Torres-Sánchez
  • Juan H. Torres-Jasso
  • Alán Y. Yáñez-González
  • Mireya Z. Reyna-Villela
  • Daniel Rojas-Bravo
  • Joel Salazar-Flores
Keywords: Naproxen brands, Dissolution, Phosphate buffer, Grapefruit, Cola drink, Milk


Purpose: To investigate the dissolution properties of various brands of naproxen in four dissolution media in order to forecast their biological availability.

Methods: Dissolution tests were carried out in a dissolution tester with 48 tablets of different naproxen brands in 900 mL of 0.1 M phosphate buffer, pH 7.4. Subsequently, the medium was modified with 600 mL of buffer plus 300 mL of cola drink, grapefruit or milk. Each sample was taken and brought to a concentration approximating that of a reference solution. Absorbance at 332 nm was determined and the dissolution, Q, was calculated (Q values ≥ 80.0 ± 5 % were acceptable).

Results: Dissolution in buffer was > 85 %. In cola drink, it was < 80 %, while in grapefruit juice, it was in the range of 7 - 68 %. Using 2-way ANOVA, these media and the three naproxen brands showed significant differences (F = 68.90, p = 0.0000; F = 23.18, p = 0.0000). With Fisher's LSD test, two of these media contributed consistently to dissolution, and the three drug brands showed statistically different dissolution profiles (p ≤ 0.05).

Conclusion: Caution must be exercised cola drink, grapefruit juice and milk are used to administered naproxen as the biological availability of the drug may be altered.


Journal Identifiers

eISSN: 1596-9827
print ISSN: 1596-5996