If i take clonazepam once a week at most (0.5 mg) for sleep will i have any problems stopping? cardiologist prescribed, tachycardia causes insomnia

No problems: Physician dependence will not develop taking Clonazepam 0.5mg one per week.

Yes, this can cause: Physical dependence. The research on benzodiazepines shows the window of opportunity is around 6 months. After this time anxiety rebound effect is likely when trying to stop clonazepam. However, from my experience not likely you will become addicted or dependent with o 0.5 mg/week. Rec.: if concerned, talk to your prescribing physician for more information