There is such a thing called valerian root which helps people with sleep disorders and anxiety. As with any substance out there you should always be careful. Maybe talk to your doctor first about it.
I'm a little wary about the idea of substituting another drug for one you want to stop using... There are some instances where that makes sense to me, like methadone maintenance for heroin addicts. Heroin is a dangerous drug and heroin addicts might engage in risky behaviors like needle sharing, so it makes sense to use something else that is less dangerous and not as prone to abuse since it doesn't give the same "high" feeling. But Valium, while very addictive, isn't very toxic...so I don't know that there are a lot of safer alternatives. And I think it's really important to recognize that just because something is "natural" doesn't mean it's safe. There are a lot of natural poisons and natural addictive substances.
Yyou really should only stop taking it under a doctor's supervision (like it says on the bottle or the included information if you have a prescription) because withdrawal symptoms can be pretty severe. It's probably not a good idea to try substituting some other substance on your own.
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