I think it’s over 5 years old!
Henna is an herb, so like any old herbs it will lose potency. It might still work, it might not. If it is in powder form, it won’t hurt your hair if you try, it just might not do anything.
If it’s not in powder form, I cannot really help.
The cassia I bought a while ago had an expiration date, and I bet regular henna which dyes the hair would as well. Get some fresh henna just in case.
“Henna powder has a shelf life of only a few months, and even less if stored in a warm place. ”
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