Tropical Journal of Pharmaceutical Research
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Adsorptive property of kaolin in some drug formulations

Anthony O Onyekweli1F, Cyril O Usifoh2, Lucky O Okunrobo2  and Jessica D Zuofa1

1Department of Pharmaceutics and Pharmaceutical Technology, and 2Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Benin, Benin-City, Nigeria

Tropical Journal of Pharmaceutical Research 2003; 2(1): 155-159

Abstract  Full Text

Purpose: Kaolin is a known adsorbent, has lubricant property in powders and is therefore proposed as a lubricant in tablet formulations. This study was carried out to evaluate whether kaolin can adsorb some active drugs when mixed with them in tablet formulations even at very low concentrations.

Method: Chloroquine and chlorpheniramine tablets were formulated with powder mixtures containing various concentrations of kaolin. The effect of kaolin on the physical properties of the tablets were examined and compared with those of standard lubricants like magnesium stearate and talc. Chloroquine and chlorpheniramine tablets and powders of amoxicillin/clavulanic acid oral powder and ampicillin/cloxacillin injection were also mixed with and without various concentrations of kaolin in water. Chemical assay of the drugs in the solutions were determined over time.

Results: Kaolin significantly reduced the amount of each of the drugs in the solutions containing kaolin.

Conclusion: Kaolin reduces the amount of some drugs when incorporated in drug formulations. Therefore, its inclusion in such drug formulations should not be encouraged.

Keywords: Adsorption, ampicillin/cloxacillin, amoxicillin/clavulanic acid, chloroquine, chlorpheniramine, drug formulation, kaolin.

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Last updated: August 19, 2003