Confidence votes 76. It depends on the temperature of the refrigerator and how well the pack is resealed. Three to ten days depending on the environment.
Pediatric Patients: Klonopin is administered orally. In order to minimize drowsiness, the initial dose for infants and children (up to 10 years of age or 30 kg of body weight) should be between 0.01 and 0.03 mg/kg/day but not to exceed 0.05 mg/kg/day given in two or three divided doses.
It can be great for sleep when needed. I take Klonopin on a PRN basis to avoid tolerance and dependance issues. The drug seems to last about 6-8 hours for me. This drug is VERY cheap, only costing about $25 a refill for 120mgs. This was my favourite drug before the godly Adderall XR came by me.