Health Benefits of Bishop's Weed

bishop's weed

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Bishop's weed (Ammi majus) is a plant used in herbal medicine. Available in dietary supplement form, it's sometimes referred to as bishop's flower or lady's lace. Bishop's weed is most often used in the treatment of skin disorders.

Bishop's Weed and Skin Health

Bishop's weed contains methoxsalen, a compound used in the treatment of such skin conditions as psoriasis, tinea versicolor, and vitiligo. Methoxsalen is classified as a psoralen, a type of compound that increases the skin's sensitivity to ultraviolet light.

When taken orally or applied topically (i.e., directly to the skin), methoxsalen is known to alter skin cells in a way that promotes the production of melanin (a natural substance that gives color to the skin) in response to ultraviolet light exposure. In a medical procedure known as PUVA therapy (which stands for "psoralen-UVA therapy"), patients receive methoxsalen and are then exposed to ultraviolet light. PUVA therapy is typically used in the treatment of such conditions as eczema, psoriasis, vitiligo, and cutaneous T cell lymphoma.

Today, prescription drugs used in PUVA therapy generally contain methoxsalen produced in the laboratory (rather than compounds sourced from bishop's weed).

More Uses

In alternative medicine, bishop's weed is also touted as a natural remedy for a number of other health conditions, including:


Although a number of studies published in the mid-20th century suggest that bishop's weed may aid in the treatment of vitiligo, more recent research on bishop's weed's health effects is lacking.

The latest research on bishop's weed includes a preliminary study published in Organic and Medicinal Chemistry Letters in 2012, which found that certain compounds found in bishop's weed may help reduce inflammation and fight off viruses. More research is needed to determine whether bishop's weed can be recommended in the treatment of any health condition.


Because few studies have tested the health effects of dietary supplements containing bishop's weed, little is known about the safety of long-term or regular use of this herb. However, there's some concern that bishop's weed may trigger such side effects as headache, nausea, and vomiting.

Since bishop's weed changes the way your skin cells react to exposure to ultraviolet light, some medical experts warn that use of bishop's weed may increase sensitivity to the sun and, in turn, raise your risk of skin cancer.

Additionally, bishop's weed may cause liver conditions to worsen, as well as inhibit blood clotting.

Keep in mind that supplements haven't been tested for safety and dietary supplements are largely unregulated. In some cases, the product may deliver doses that differ from the specified amount for each herb. In other cases, the product may be contaminated with other substances such as metals. Also, the safety of supplements in pregnant women, nursing mothers, children, and those with medical conditions or who are taking medications has not been established.


Several natural remedies may help reduce symptoms of psoriasis. For example, some research shows that following a diet rich in omega-3 fatty acids (found naturally in flaxseed and fish oil) may be beneficial for psoriasis patients. Additionally, there's some evidence that applying creams containing aloe vera or capsaicin may help soothe psoriasis symptoms.

You can also ease symptoms of psoriasis by practicing stress management techniques, avoiding alcohol consumption, and taking daily baths with such substances as Epsom salts and colloidal oatmeal added to the bath water.​

While research on the use of natural remedies in the treatment of vitiligo is fairly limited, an herb known as ammi visnaga shows promise in the treatment of this skin condition.

Where to Find It

You can purchase dietary supplements containing bishop's weed from some natural-foods stores and online stores specializing in herbal products.

Using Bishop's Weed for Health

It's also important to note that self-treating a skin condition with bishop's weed and avoiding or delaying standard care may have serious consequences. Talk to your doctor if you're considering the use of bishop's weed in the treatment of a skin disorder (or any other condition).

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Article Sources

  • Bethea D, Fullmer B, Syed S, Seltzer G, Tiano J, Rischko C, Gillespie L, Brown D, Gasparro FP. "Psoralen photobiology and photochemotherapy: 50 years of science and medicine." J Dermatol Sci. 1999 Feb;19(2):78-88.
  • Ekiert H, Gomółka E. "Coumarin compounds in Ammi majus L. callus cultures." Pharmazie. 2000 Sep;55(9):684-7.
  • Selim YA, Ouf NH. "Anti-inflammatory new coumarin from the Ammi majus L." Org Med Chem Lett. 2012 Jan 12;2(1):1.