Chickweedis a perennial flowering plant used in traditional Chinese medicine to treat skin diseases and viruses.
That means some supplement products may not contain what the label says.
There are no human clinical trials showing benefits from chickweed for these or other uses.

Verywell / Anastasia Tretiak
Studies performed in test tubes or using animal models do not necessarily translate into benefits for humans.
Therefore robust clinical trials in humans are certainly needed before chickweed can be recommended for these or other conditions.
Chickweed Supplement Facts
What Are the Side Effects of Chickweed?
Very little is known about the safety profile of chickweed.
If you decide to take it, be alert for possible side effects.
These side effects may be common or severe.
Because human research is so sparse, there is no recommended chickweed dose.
If you decide to try chickweed, follow the manufacturer’s recommended dose.
What Happens If I Take Too Much Chickweed?
Never take chickweed at doses higher than recommended by the supplement manufacturers.
Discard after one year or as directed by the manufacturer.
Here are some ways it can be incorporated into your diet.
The plant is dispersed worldwide.
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Centers for Disease Control and Prevention.Nitrates/Nitrites poisoning.
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