Reviewed on 6/11/2021
Other Name(s):

Ammi, Ammi daucoides, Ammi visnaga, Ammi Visnage, Bischofskrautfruchte, Bishop's Weed, Bishop's Weed Fruit, Biznaga, Daucus visnaga, Fenouil Annuel, Fruits de Khella, Herbe aux Cure-Dents, Herbe aux Gencives, Khellin, Khelline, Noukha, Toothpick Ammi, Toothpick Plant, Visnaga, Visnagae, Visnagafruchte, Visnaga Fruit, Visnagin.


Khella is a plant. The dried, ripe fruit is used to make medicine. People commonly prepare an “extract” by removing khellin, one of the active chemicals in khella, and dissolving it in a liquid that is then used as medicine. Khella is less commonly prepared as a tea.

Khella is used for respiratory conditions including asthma, bronchitis, cough, and whooping cough.

It is also used for diseases of the heart and blood vessels (cardiovascular disorders) including high blood pressure, irregular heartbeat (arrhythmias), congestive heart failure (CHF), chest pain (angina), “hardening of the arteries” (atherosclerosis), and high cholesterol.

Other uses include treatment of diabetes, colic and abdominal cramps, liver and gallbladder disorders, kidney stones, and fluid retention.

Women sometimes use khella for menstrual pain and premenstrual syndrome (PMS).

Some people apply khellin taken from khella directly to the skin and then expose the area to light to treat skin problems such as vitiligo, psoriasis, and patchy hair loss (alopecia areata).

It is also put on the skin to treat wounds, skin redness and swelling (inflammation), and poisonous bites.

Be careful not to confuse khella with its less commonly used relative, bishop's weed. The two species contain some of the same chemicals and work similarly in the body, but khella is more commonly used for heart and lung conditions, and bishop's weed is more commonly used for skin conditions.

How does it work?

Khella contains substances that seem to relax and widen blood vessels; decrease heart contraction; open up the lungs; increase “good cholesterol” (HDL, high-density lipoprotein); and fight bacteria, viruses, and fungi.

Several prescription drugs including amiodarone, nifedipine, and cromolyn have been developed from khella.


Next to red peppers, you can get the most vitamin C from ________________. See Answer

Uses & Effectiveness

Insufficient Evidence to Rate Effectiveness for...

  • Psoriasis: Early research suggests that taking khellin, a chemical in khella, by mouth in combination with sunlight exposure helps clear skin sores in people with psoriasis.
  • A skin discoloration disorder called vitiligo. Research on the effects of khella for treating vitiligo shows conflicting results. Some research shows that taking khellin, a chemical in khella, by mouth or applying it to the skin improves skin discoloration when used along with ultraviolet light therapy. However, other research shows that applying khellin to the skin along with sunlight exposure doesn't improve skin discoloration. Also, some research shows that khellin therapy requires longer treatment durations and higher light doses to improve skin discoloration similarly to the effects of psoralen plus ultraviolet light therapy (PUVA).
  • Stomach cramps.
  • Kidney stones.
  • Menstrual cramps.
  • Premenstrual syndrome (PMS).
  • Asthma.
  • Bronchitis.
  • Cough.
  • Whooping cough.
  • High blood pressure.
  • Irregular heartbeat (arrhythmias).
  • Congestive heart failure (CHF).
  • Chest pain (angina).
  • “Hardening of the arteries” (atherosclerosis).
  • High cholesterol.
  • Other conditions.
More evidence is needed to rate the effectiveness of khella for these uses.

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).

Side Effects

Khella is POSSIBLY UNSAFE when taken in high doses or used for a long time. It can cause side effects including liver problems, nausea, dizziness, constipation, lack of appetite, headache, itching, trouble sleeping, and skin sensitivity to sunlight (photosensitization).


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Special Precautions & Warnings

Pregnancy and breast-feeding: it's LIKELY UNSAFE to take khella if you are pregnant. It contains khellin, a chemical that can cause the uterus to contract. This might cause a miscarriage.

It's also best to avoid khella if you are breast-feeding. There isn't enough information to know if it is safe for the nursing infant.

Liver disease: Khella might make liver disease worse. Don't use it if you have liver problems.


Digoxin (Lanoxin)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Digoxin (Lanoxin) helps the heart beat more strongly. Khella seems to slow the heartbeat. Taking khella along with digoxin might decrease the effectiveness of digoxin. Do not take khella if you are taking digoxin (Lanoxin).

Medications that can harm the liver (Hepatotoxic drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Khella might harm the liver. Taking khella along with medication that might also harm the liver can increase the risk of liver damage. Do not take khella 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.

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. Khella might also increase your sensitivity to sunlight. Taking khella 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 khella 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 khella. 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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