Stinging Nettle Dosage
There is no standard recommended dosage of stinging nettle, as various products may contain different amounts of the active ingredient. In one study where the supplement was used for treating allergies, a dose of 300 mg was used three times daily. Since only vague "trial and error" information is available, you should follow the dosing instructions on the label of your particular product.
As is the case with natural products and herbal supplements, there is simply not enough quality information available to recommend a safe and effective dosage for stinging nettle at this time. As a result, much of the available information for dosing stinging nettle comes from practical experience with the supplement.
There are a few different reasons why it is difficult to recommend a stinging nettle dosage. First, there are several different ways that the herb is used and various different types of stinging nettle products. Even products that have the same "strength" (in milligrams) may contain different amounts of the various active components of stinging nettle.
Second, because herbal supplements and foods do not need FDA approval, studies to find the safest and most effective dosages for dietary supplements or foods are rarely performed. Without such studies, typically, only vague "trial and error" information is available. Even if good dosing information were available, there may be significant variability of the content, purity, and strength among different brands of the same herbal supplement, making consistently safe and effective dosing difficult.
For treating arthritis, one study had success using fresh nettle leaves to "sting" the arthritic joint once daily. For allergy treatment, a dose of 300 mg of stinging nettle extract three times a day is sometimes suggested. For treating an enlarged prostate, studies have used various doses, such as 80 mg three times daily or 120 mg twice daily (in combination with other herbs). There is no guarantee that these doses are the safest or most effective doses for these uses.