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Other Names:

Berce Commune, Berce Laineuse, Berce Très Grande, Cow Cabbage, Cow Parsnip, Heracleum lanatum, Heracleum maximum, Heracleum montanum, Heracleum sphondylium, Heracleum sphondylium subsp. montanum, Hogweed, Imperatoria, Madnep, Radix Pimpin...
See All Names

MASTERWORT Interactions
MASTERWORT Overview Information

Masterwort is a plant. People use it to make medicine.

Despite safety concerns, people take masterwort for relief of muscle cramps, stomach disorders, digestive problems, diarrhea, and swelling of the tissue that lines the stomach and intestines.

There have been some reports that masterwort is used as a replacement to “stretch” greater burnet-saxifrage (Pimpinella major) products.

How does it work?

There is not enough information to know how masterwort might work.

MASTERWORT Uses & Effectiveness What is this?

Insufficient Evidence for:

  • Muscle cramps.
  • Stomach disorders.
  • Digestion problems.
  • Diarrhea.
  • Swelling (inflammation) of the lining of the stomach and intestines.
  • Other conditions.
More evidence is needed to rate the effectiveness of masterwort for these uses.

MASTERWORT Side Effects & Safety

Masterwort is POSSIBLY UNSAFE when taken by mouth or applied to the skin. It can cause the skin to burn more easily in the sun. Wear protective clothing and sunblock outside, especially if you are light-skinned. Also, there are some chemicals in masterwort that can cause cancer.

Special Precautions & Warnings:

Pregnancy and breast-feeding:If you are pregnant, it’s LIKELY UNSAFE to take masterwort by mouth, especially in early pregnancy. It might start your menstrual period, and that could cause a miscarriage.

It is POSSIBLY UNSAFE to take masterwort by mouth if you are breast-feeding. It’s best to avoid use.

Exposure to ultraviolet (UV) light including sunlamp treatment for certain skin conditions such as psoriasis, use of tanning beds, or time in sunlight: Masterwort causes sensitivity to ultraviolet (UV) light. It could cause your skin to burn. Don’t use masterwort if you are receiving UV light therapy. Also, stay out of the sun and avoid tanning beds if you are taking masterwort.

MASTERWORT Interactions What is this?

Moderate Interaction Be cautious with this combination

  • Medications that increase sensitivity to sunlight (Photosensitizing drugs) interacts with MASTERWORT

    Some medications can increase sensitivity to sunlight. Masterwort might also increase your sensitivity to sunlight. Taking masterwort along with medication that increase sensitivity to sunlight could increase the chances of sunburn, blistering or rashes on areas of skin exposed to sunlight. Be sure to wear sunblock and protective clothing when spending time in the sun.
    Some drugs that cause photosensitivity include amitriptyline (Elavil), Ciprofloxacin (Cipro), norfloxacin (Noroxin), lomefloxacin (Maxaquin), ofloxacin (Floxin), levofloxacin (Levaquin), sparfloxacin (Zagam), gatifloxacin (Tequin), moxifloxacin (Avelox), trimethoprim/sulfamethoxazole (Septra), tetracycline, methoxsalen (8-methoxypsoralen, 8-MOP, Oxsoralen), and Trioxsalen (Trisoralen).


The appropriate dose of masterwort depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for masterwort. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.

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Conditions of Use and Important Information: This information is meant to supplement, not replace advice from your doctor or healthcare provider and is not meant to cover all possible uses, precautions, interactions or adverse effects. This information may not fit your specific health circumstances. Never delay or disregard seeking professional medical advice from your doctor or other qualified health care provider because of something you have read on WebMD. You should always speak with your doctor or health care professional before you start, stop, or change any prescribed part of your health care plan or treatment and to determine what course of therapy is right for you.

This copyrighted material is provided by Natural Medicines Comprehensive Database Consumer Version. Information from this source is evidence-based and objective, and without commercial influence. For professional medical information on natural medicines, see Natural Medicines Comprehensive Database Professional Version. © Therapeutic Research Faculty 2009.

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