The present invention relates to a composition comprising pharmaceutical active ingredients which are susceptible to, or have potential for, abuse. The invention provides an oral pharmaceutical composition comprising a first population of beads and a second population of beads. The first bead population comprises a pharmaceutically active ingredient susceptible to, or having the potential for, abuse. The second bead population comprises a gelling agent and a coating substantially surrounding the gelling agent, but containing no pharmaceutically active ingredient. The first bead population and the second bead population are physically separable, but visually indistinguishable to the naked eye. Upon ingress of water into the second population of beads, the gelling agent is caused to swell forming a viscous mass inhibiting or preventing the extraction of the active ingredient.
