Caroverine (Spasmium, Tinnitin, Tinnex) is a muscle-relaxing drug used in Austria and Switzerland to relieve spasms in smooth muscles (which include intestines, arteries, and other organs), and the use in those countries was extended to aid with cerebrovascular diseases there, and eventually to treat tinnitus.

[1] Pharmacologically, it has been described as a nonspecific calcium channel blocker and as an antagonist of both non-NMDA and NMDA glutamate receptors.

[5] An intravenous formulation was tested in a single-blinded study in tinnitus that published in 1997 and had positive results; an effort to replicate those results failed to show any effect,[4] and more people had their condition worsen than experienced benefit.

[6] In 2010 Phafag licensed rights to caroverine to the Indian company, Lincoln Pharmaceuticals, to develop the drug for tinnitus in India.

[8] As of 2016 it had been studied in a small clinical trial in people with loss of the sense of smell.