I was wondering if the same basic principles of cold water extraction would hold true for Robitussin AC. I have recently been prescribed a bottle of this, of which the contents are Codeine phosphate and guaifenisin. Will the guaifenisin form crystaline structures when chilled? SWIM's basic idea was to take the cough syrup, chill it in an ice bath for 5-10 minutes, and then pour the syrup through a coffee filter in order to separate the guaf, assuming it crystalizes. Would this work?