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AAPS PharmSciTech. 2004 March; 5(1): 29.
Published online 2009 November 27. doi:  10.1208/pt050106
PMCID: PMC2784857

Comparison of the dissolution of metaxalone tablets (Skelaxin) usingUSP apparatus 2 and 3


The purpose of this study was to evaluate the effect of pH on the dissolution behavior of metaxalone in the marketed product Skelaxin tablets. The dissolution was evaluated using United States Pharmacopeia (USP) dissolution Apparatus 2 and 3 at pHs ranging from 1.5 to 7.4 Results from these studies show that the dissolution of this product is pH dependent. At low pH (simulated gastric fluid, pH 1.5), the dissolution of metaxalone from Skelaxin tablets, was less than 10% over 75 minutes; whereas, dissolution at pH 4.5 showed greater than 90% release in the same time period. These results were consistent for both Apparatus 2 and 3. This suggests that Skelaxin Tablets should be considered a delayed release dosage form.

KeyWords: Metaxalone, dissolution, pH dependence, apparatus 3

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.
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8. American Society of Health-System Pharmacists.AHFS Drug Information 2001. Bethesda, MD: American Society of Health-System Phamacists; 2001.

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