Valium vs Clonazepam — Both medications are benzodiazepines used to relieve anxiety, but they differ in onset, duration, and potency. Valium (diazepam) works quickly, offering fast relief within 15–60 minutes, making it more suitable for acute or situational anxiety. Clonazepam (Klonopin), in comparison, has a slower onset but delivers longer-lasting effects, typically lasting 8–12 hours—making it better suited for ongoing, chronic anxiety or panic control. Clonazepam is more potent—requiring lower doses for similar effects—and often preferred when a steady, prolonged anxiolytic effect is desired.