What are the side effects of mixing Klonopin with alcohol?

Absolutely not. Klonopin® (generic: clonazepam), a member of the benzodiazepine class, and alcohol mixed together increases the effect of both substances and acts as a central nervous system depressant. The central nervous system includes the brain stem, the part of your brain that regulates things like respiratory and cardiac rates. It is not unusual for someone to stop breathing and either die or incur permanent brain damage from this combination.

Mixing alcohol and benzodiazepines (like Klonopin®) can be lethal.