Taking clonazepam 0.5mg daily in evening for last 8 days. at what point should it be switched to an ssri to avoid addiction issues?

2 wks, roughly: There's no exact answer, as tolerance to benzodiazepine tranquilizers happens gradually. As a very rough estimate, taking a medication like Clonazepam consistently for longer than 2 weeks usually results in some withdrawal symptoms if stopped suddenly. It's also dose related, and 0.5 mg daily isn't a lot. Best to take addiction risk seriously, but try not to stress over it. Ask your doctor.

Talk with your MD: Typically, people are started on an ssri with Clonazepam for the treatment of anxiety. Ssris are the first line treatment, but they typically take several weeks or more before they start working. Therefore, Clonazepam is often prescribed as a bridge to be used until ssri starts working. Once ssri starts working, then Clonazepam can be weaned if your doctor thinks that is appropriate.