The Health Benefits of Bishop's Weed

bishop's weed

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

The term bishop's weed refers to several similar plants. Ammi majus should not be confused with Trachyspermum ammi, also called ajwan or carom, which is used in Ayurvedic medicine, or Ammi visnaga, commonly referred to as khella.

Despite bishop's weed's purported health benefits, there is limited scientific evidence to support its medical use.

Health Benefits

Bishop's weed has been used to treat health conditions dating back to 2000 B.C.E. in Egypt. However, there is a lack of modern research to support these health claims.

Skin Conditions

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

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.

Anti-Viral Properties

A preliminary study on bishop's weed published in Organic and Medicinal Chemistry Letters in 2012 found that certain compounds 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.

Selection, Preparation & Storage

There isn't enough scientific evidence to support the use of bishop's weed for any health issues, so there is no recommended dose. Follow the instructions on the label and speak to your healthcare provider.

When purchasing bishop's weed, check the label for its scientific name, Ammi majus. Do not confuse it with the spice ajwain (carom), which is from the plant Trachyspermum ammi, or khella, which comes from the plant Ammi visnaga.

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.

Possible Side Effects

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, 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.

People who are taking medications changed by the liver should use caution when taking bishop's weed. These drugs include Mevacor (lovastatin), Nizoral (ketoconazole), Sporanox (itraconazole), Allegra (fexofenadine), and Halcion (triazolam), among others.

Bishop's weed should not be used with drugs that cause photosensitivity, including Elavil, (amitriptyline), Cipro (ciprofloxacin), Noroxin (norfloxacin), Maxaquin (lomefloxacin), Floxin (ofloxacin), Levaquin (levofloxacin), and tetracycline, among others.

Bishop's weed may slow blood clotting and should not be taken along with other medications that slow clotting, including aspirin, Plavix (clopidogrel), diclofenac, ibuprofen (Advil, Motrin, etc.), naproxen (Naprosyn, Aleve, etc), Lovenox (enoxaparin), Coumadin (warfarin), and heparin, among others.

The safety of supplements in pregnant women, nursing mothers, children, and those with medical conditions or who are taking medications has not been established.

Common Questions

Is bishop's weed a spice?

Ammi majus, commonly known as bishop's weed, is not a spice. However, another plant also called bishop's weed, Trachyspermum ammi, is the Indian spice known as ajwain or carom. Ajwain is used in Ayurvedic medicine and can be found as an ingredient in herbal teas.

Can you use bishop's weed treat vitiligo?

Bishop's weed has been used as a folk remedy to treat vitiligo by making a tea, mixing with a little honey and olive oil, applying it to the skin and spending 10 minutes in the late-day sun. However, this is not recommended. The plant contains psoralens, substances that react with ultraviolet (UV) light to darken skin, but doing so can result in phytophotodermatitis, a painful skin reaction that results in blisters and scarring 24 to 48 hours after exposure.

A Word From Verywell

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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