What is a natural alternative to lorazepam?

Let go the thoughts. Careful with lorazepam. It can cause ups and downs of anxiety and physical dependence. Antidepressants are the best choice for anxiety. Cognitive therapy (buy a self-help book at amazon for an introduction) and meditation practice are crucial. In cognitive therapy, you address distortions of thinking. In meditation, you practice let go the hand of thought (buy zen mind, beginner mind at amazon).
Check with your doc. Lorazepam has too many side effects. Valerian may be better for you but check with your doc.