Would you like to give us more information on the tea you are considering? Are you only trying to pee more?
The tea is likely safe if it is from a reputable source. I would be concerned about the ingredients, following the directions, and drinking plenty of water. If your goal is just peeing more, you could also drink normal tea, green tea, or any regular herbal tea known to be safe. A big glass off iced tea will make you go also. So will a quart of water.
A diuretic can dehydrate a person if used too much. A natural tea does not have the diuretic ingredients tightly controlled like medications. It could be possible to take too much and cause a problem if someone is not careful. It would be used by people who have too much water in their body. Too much of it would make the body get rid of too much water. Not safe.
A person will naturally pee more if they drink more liquids. The safest option is pure water. The next safest is lightly flavored water like apple juice. My favorite beverages, caffeinated beverages, have caffeine which is both a diuretic and a stimulant. A person should also consider drinking water with these to prevent dehydration. These are considered safe in reasonable quantities.
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