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.
How it works
Bishop's weed contains several chemicals, including methoxsalen, a chemical used to make a prescription medication for the skin condition psoriasis.
Not ProvenSkin conditions such as psoriasis and vitiligoDigestive problemsAsthmaChest painKidney stonesFluid retentionOther conditions
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.
Pregnancy and breast-feeding: It'sUNSAFEto use bishop's weed if you arepregnant. It contains a chemical called khellin that can cause theuterusto contract, and this might threaten thepregnancy.Are there any interactions with medications?
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.
ModerateMedications that slow blood clotting (Anticoagulant/Antiplatelet drugs)
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.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.Some medications that can harm the liver include acetaminophen (Tylenol and others), amiodarone (Cordarone), carbamazepine (Tegretol), isoniazid (INH), methotrexate (Rheumatrex), methyldopa (Aldomet), fluconazole (Diflucan), itraconazole (Sporanox), erythromycin (Erythrocin, Ilosone, others), phenytoin (Dilantin), lovastatin (Mevacor), pravastatin (Pravachol), simvastatin (Zocor), and many others.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.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).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.Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others.