What Is Klonopin (Clonazepam) 1 mg? Klonopin is the brand name for clonazepam, a long-acting benzodiazepine. The 1 mg tablet is one of the common strengths available (others include 0.5 mg and 2 mg). Benzodiazepines enhance the effect of gamma-aminobutyric acid (GABA), the brain’s primary