Benzos and alcohol are the only two classes of drugs that can kill you when withdrawing from them.
I'll try to keep it simple. Benzos (and alcohol) work by making a neurotransmitter, GABA, more effective when it binds to the brain. GABA basically reduces how strong/powerful nerve impulses are, so when you're anxious and on edge, these drugs will sedate and chill you out by reducing the excitability of the brain cells associated with anxiety, muscle stiffness, etc.
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