Another cough preparation: carbetapentane

While researching for other non-narcotic cough medications, I came across carbetapentane.  A Pubmed search produced very little evidence for its effectiveness or safety.  In 2007, the FDA did rule that carbetapentane should not be sold in over-the-counter products because the doses were too low to produce any benefit. Clinically, it is available in several products with other ingredients, such as Exall, Levall, and Corzall.  I have no experience with these, although I will be attempting to gain some experience, if the proper situation should arise.