The terms proximal (from Latin proximus, meaning 'nearest') and distal (from Latin distare, meaning 'to stand away from') are used to describe parts of a feature that are close to or distant from the main mass of the body, respectively.
But, with Citrucel and/or Metamucil you can start with one teaspoon mixed in water or juice. If you have diarrhea don't use the preparation with artificial sweeteners. Use the one with sugar. I think artificial sweeteners (some of them) might cause more diarrhea.
Metamucil. According to WebMD, it's safe to use Metamucil for cats and is especially useful for cats that suffer from frequent constipation. The site recommends adding one teaspoon per day to wet cat food, and that you can keep your cat on this regimen indefinitely without causing a problem.