What other names is Bishop’s Weed known by?
Ajava Seeds, Ajowan, Ajowan Caraway, Ajowan Seed, Ajowanj, Ajwain, Ajwan, Ameo Bastardo, Ammi Commun, Ammi Élevé, Ammi glaucifolium, Ammi Inodore, Ammi majus, Ammi Officinal, Bishop’s Flower, Bisnague, Bullwort, Carum, Espuma del Mar, Flowering Ammi, Grand Ammi, Omum, Yavani.
What is Bishop’s Weed?
Bishop’s weed is a plant. The seeds are used to make medicine.
The prescription drug methoxsalen (Oxsoralen, Methoxypsoralen) was originally prepared from bishop’s weed, but it is now made in the laboratory. Methoxsalen is used to treat psoriasis, a skin condition.
Bishop’s weed is used for digestive disorders, asthma, chest pain (angina), kidney stones, and fluid retention.
Some people apply bishop’s weed directly to the skin for skin conditions including psoriasis and vitiligo.
Be careful not to confuse bishop’s weed (Ammi majus) with its more commonly used relative, khella (Ammi visnaga). The two species do contain some of the same chemicals and have some similar effects in the body. But Bishop’s weed is more commonly used for skin conditions, and khella is usually used for heart and lung conditions.
Insufficient Evidence to Rate Effectiveness for.
- Skin conditions such as psoriasis and vitiligo.
- Digestive problems.
- Chest pain.
- Kidney stones.
- Fluid retention.
- Other conditions.
More evidence is needed to rate the effectiveness of bishop’s weed for these uses.
How does Bishop’s Weed work?
Bishop’s weed contains several chemicals, including methoxsalen, a chemical used to make a prescription medication for the skin condition psoriasis.
Are there safety concerns?
There isn’t enough information to know if bishop’s weed is safe. When taken by mouth, bishop’s weed might cause nausea, vomiting, and headache. Some people are allergic to bishop’s weed. They can get a runny nose, rash, or hives. There is also some concern that bishop’s weed might harm the liver or the retina of the eye.
Bishop’s weed can cause skin to become extra sensitive to the sun. This might put you at greater risk for skin cancer. Wear sunblock outside, especially if you are light-skinned.
Special Precautions & Warnings:
It’s also best to avoid using bishop’s weed if you are breast-feeding. There isn’t enough information to know whether it is safe for a nursing infant.
Liver disease: There is some evidence that bishop’s weed might make liver disease worse.
Surgery: Bishop’s weed might slow blood clotting. There is a concern that it might increase the risk of bleeding during and after surgery. Stop using bishop’s weed at least 2 weeks before a scheduled surgery.
Are there any interactions with medications?
Some medications are changed and broken down by the liver. Bishop’s weed might decrease how quickly the liver breaks down some medications. Taking bishop’s weed along with some medications that are broken down by the liver can increase the effects and side effects of some medications. Before taking bishop’s weed, talk to your healthcare provider if you are taking any medications that are changed by the liver.
Some medications changed by the liver include lovastatin (Mevacor), ketoconazole (Nizoral), itraconazole (Sporanox), fexofenadine (Allegra), triazolam (Halcion), and many others.
Medications that can harm the liver (Hepatotoxic drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Bishop’s weed might harm the liver. Taking bishop’s weed along with medication that might also harm the liver can increase the risk of liver damage. Do not take bishop’s weed if you are taking a medication that can harm the liver.
Medications that increase sensitivity to sunlight (Photosensitizing drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Some medications can increase sensitivity to sunlight. Bishop’s weed might also increase your sensitivity to sunlight. Taking bishop’s weed along with medication that increases 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.
Medications that slow blood clotting (Anticoagulant/Antiplatelet drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.
Bishop’s weed might slow blood clotting. Taking bishop’s weed along with medications that also slow clotting might increase the chances of bruising and bleeding.
Dosing considerations for Bishop’s Weed.
The appropriate dose of bishop’s weed 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 bishop’s weed. 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.
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).
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Dollahite, J. W., Younger, R. L., and Hoffman, G. O. Photosensitization in cattle and sheep caused by feeding Ammi majus (greater Ammi; Bishop’s-Weed). Am J Vet.Res 1978;39(1):193-197. View abstract.
EL MOFTY, A. M. Observations on the use of Ammi majus Linn. In vitiligo. Br J Dermatol 1952;64(12):431-441. View abstract.
EL MOFTY, A. M., el Sawalhy, H., and el Mofty, M. Clinical study of a new preparation of 8-methoxypsoralen in photochemotherapy. Int J Dermatol 1994;33(8):588-592. View abstract.
Kavli, G. and Volden, G. Phytophotodermatitis. Photodermatol. 1984;1(2):65-75. View abstract.
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Abdel-Fattah A, Aboul-Enein MN, Wassel GM, El-Menshawi BS. An approach to the treatment of vitiligo by khellin. Dermatologica 1982;165:136-40. View abstract.
Ahsan SK, Tariq M, Ageel AM, et al. Effect of Trigonella foenum-graecum and Ammi majus on calcium oxalate urolithiasis in rats. J Ethnopharmacol 1989;26:249-54. View abstract.
Bethea D, Fullmer B, Syed S, et al. Psoralen photobiology and photochemotherapy: 50 years of science and medicine. J Dermatol Sci 1999;19:78-88. View abstract.
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Bishop’s Weed What other names is Bishop’s Weed known by? Ajava Seeds, Ajowan, Ajowan Caraway, Ajowan Seed, Ajowanj, Ajwain, Ajwan, Ameo Bastardo, Ammi Commun, Ammi Élevé, Ammi glaucifolium,
The Health Benefits of Bishop’s Weed
Used to treat skin issues, supporting research is lacking
Cathy Wong is a nutritionist and wellness expert. Her work is regularly featured in media such as First For Women, Woman’s World, and Natural Health.
Meredith Bull, ND, is a licensed naturopathic doctor with a private practice in Los Angeles. She helped co-author the first integrative geriatrics textbook, “Integrative Geriatric Medicine.”
Verywell / Anastasia Tretiak
Bishop’s weed (Ammi majus) is a common garden plant sometimes used in herbal medicine. It is most often used in the treatment of skin disorders such as psoriasis and vitiligo because it contains a compound that may help skin be more responsive to light therapy.
But despite bishop’s weed’s purported health benefits, there is limited scientific evidence to support its medical use.
Also Known As
- Bishop’s flower
- Lace flower
- Lady’s lace
The term bishop’s weed is actually used to refer to several similar plants. Ammi majus should not be confused with Trachyspermum ammi (a.k.a. ajwan or carom) or Ammi visnaga (a.k.a. khella).
People have been using bishop’s weed to treat health conditions as far back as 2000 B.C. in Egypt. However, more research is needed to determine whether the herb can confidently be recommended for the treatment of any health concern.
But given bishop’s weed’s composition, there is reason to think it could have some utility, particularly for skin conditions.
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 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 (UV) light exposure.
Light therapy (phototherapy) uses UV light to treat a variety of skin conditions, as it can help reduce inflammation and slow skin cell growth. One of the three main types of phototherapy—psoralen-UVA (PUVA) therapy—involves given patients methoxsalen and then exposing them 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.
A preliminary study on bishop’s weed published in Organic and Medicinal Chemistry Letters in 2012 found that coumarins, compounds in bishop’s weed, may help reduce inflammation and fight off viruses.
In addition to these, bishop’s weed contains biologically active flavonoids that have antimicrobial properties, according to a 2019 study. That study also isolated a fungus from the fruit of bishop’s weed—Aspergillus amstelodami—that was found to have antimicrobial properties.
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 regular or long-term use of this herb.
There is at least some concern that bishop’s weed may trigger such side effects as headache, nausea, and vomiting. It also poses some more specific concerns, such as the following.
Since bishop’s weed changes the way your skin cells react to ultraviolet light exposure, the herb may increase sensitivity to the sun and, in turn, raise your risk of skin cancer.
If taking bishop’s weed, it is recommended to avoid prolonged periods of sun exposure. Wear sunscreen and, ideally, protective clothing whenever going outdoors.
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.
Of note, a folk remedy for vitiligo involves mixing bishop’s weed, 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 as it can result in phytophotodermatitis, a painful skin reaction that results in blisters and scarring 24 to 48 hours after exposure.
Blood Clotting Issues
The herb may also slow blood clotting and should not be taken along with other medications that slow clotting, such as aspirin, Plavix (clopidogrel), diclofenac, Advil (ibuprofen), Aleve (naproxen), Lovenox (enoxaparin), Coumadin (warfarin), and heparin.
Tell your doctor if you take bishop’s weed prior to surgery. They may recommend that you stop taking the herb in advance of any surgical procedure due to the risk of bleeding.
Pre-existing liver conditions may be worsened with the use of bishop’s weed, so people with liver problems should speak to their doctor before taking the herb.
In addition, anyone 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.
Pregnant women should not take bishop’s weed as it may cause uterine contractions that threaten the pregnancy. In addition, children and nursing mothers should not use bishop’s weed as safety in these populations has not been established.
Selection, Preparation & Storage
Because there isn’t enough scientific evidence to support the use of bishop’s weed for any health issues, there is no recommended dose. Follow the instructions on the product label and speak to your healthcare provider about what may be right for you.
When purchasing bishop’s weed, check the label for its scientific name, Ammi majus, so as not to accidentally purchase ajwain or khella.
Supplements are largely unregulated in the United States and not assessed for safety by the U.S. Food and Drug Administration (FDA). In some cases, a product may deliver doses that differ from the specified amount for each herb. In other cases, a product may be contaminated with other substances such as metals.
To ensure quality, look for supplements that have been tested and approved by an independent third-party certifying body like the U.S. Pharmacopeia (USP), ConsumerLab, or NSF International.
Is bishop’s weed a spice?
Ammi majus is not a spice. However, Trachyspermum ammi is an Indian spice used in Ayurvedic medicine and in some herbal teas.
What does bishop’s weed look like?
There are a few different plants that go by the name bishop’s weed. The Ammi majus variety has dainty white flowers similar to Queen Anne’s lace. A summer bloomer, the plant grows best in full or partial sun during June, July, and August. It attracts bees and other beneficial pollinators.
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).
An ancient medicinal herb, bishop's weed (Ammi majus) is used to treat skin conditions such as psoriasis and vitiligo.