Khella
Also known as: Khella, Visnaga, Ammi majus, Ammi visnaga
Overview
Khella is an herbal supplement derived from the plants *Ammi visnaga* or *Ammi majus*, native to the Mediterranean region. Traditionally, it has been used for a variety of conditions including vitiligo, psoriasis, kidney stones, diabetes, asthma, and urinary tract infections. The primary active compound, khellin, is known for its vasodilative, spasmolytic, and melanocyte-stimulating properties. While its traditional uses are broad, current research primarily supports its application in vitiligo treatment due to its photosensitizing effects. However, comprehensive systematic reviews and meta-analyses are largely absent, indicating a need for more robust scientific investigation into many of its purported benefits. It is available in various forms, often used topically or orally, particularly in conjunction with UV therapy for skin conditions.
Benefits
Khella's most established benefit is in the treatment of vitiligo, where it acts as a photosensitizer to enhance melanocyte proliferation and melanin production. This effect is particularly noted when khellin is combined with UV exposure, leading to repigmentation in affected areas. While traditional uses suggest benefits for conditions like psoriasis, kidney stones, and asthma, the scientific evidence for these applications is limited and less robust. Animal studies have indicated potential in lowering cholesterol, specifically increasing HDL cholesterol, and reducing blood glucose levels. However, human studies supporting these metabolic benefits are scarce, and their clinical significance is not yet well-defined. For vitiligo, benefits typically become apparent after several weeks of consistent treatment combined with UV therapy, highlighting a gradual but documented effect.
How it works
The primary mechanism of action for khella, particularly its active compound khellin, involves photosensitization. Khellin stimulates melanocyte proliferation and melanogenesis, the process of melanin production, which is crucial for repigmentation in vitiligo. This effect is amplified by exposure to ultraviolet (UV) light. While the exact molecular targets are not fully elucidated, khellin interacts directly with melanocytes in the skin. Beyond its dermatological effects, some research suggests it may influence cardiovascular health through modulation of lipid metabolism, potentially affecting cholesterol levels. However, the specific biological pathways and molecular targets involved in these systemic effects are less understood compared to its action on melanocytes. Information regarding the absorption and bioavailability of khella compounds is also limited.
Side effects
Khella is considered possibly unsafe when consumed in high doses or for prolonged periods, primarily due to the risk of liver problems and increased photosensitivity. Common side effects include gastrointestinal issues such as nausea, constipation, and lack of appetite, along with neurological symptoms like dizziness, headache, and trouble sleeping. It can also cause itching. A significant concern is increased skin sensitivity to sunlight, which can lead to severe sunburn if not managed properly. Rare but serious side effects include liver damage, making it crucial to avoid use in individuals with pre-existing liver disease. Limited information exists on drug interactions, but caution is advised when co-administering with medications that affect liver function. Khella is contraindicated during pregnancy and breastfeeding due to the potential for uterine contractions and insufficient safety data for infants.
Dosage
Optimal dosage ranges for khella are not well-established for most conditions, and it should be used under medical supervision due to potential side effects. For vitiligo, khellin is often used in low concentrations, especially when combined with UV therapy, to minimize systemic exposure while maximizing local effect. The maximum safe dose is not clearly defined, but high doses are generally considered unsafe due to the increased risk of adverse effects, particularly liver toxicity. When used for vitiligo, khella is typically taken orally before UV exposure to facilitate its photosensitizing action. Topical formulations are also utilized to reduce systemic absorption and mitigate potential side effects. Due to limited data on absorption and bioavailability, precise dosing adjustments based on these factors are challenging. No specific cofactors are identified as necessary for its efficacy.
FAQs
Is Khella safe for long-term use?
No, khella is considered possibly unsafe for long-term or high-dose use due to the risk of liver problems and increased sensitivity to sunlight. It should be used under medical supervision.
Can Khella be used during pregnancy?
No, khella is contraindicated during pregnancy and breastfeeding due to the potential for uterine contractions and a lack of sufficient safety data for infants.
How long does it take to see results for vitiligo?
For vitiligo, benefits are typically observed after several weeks of consistent treatment with khella, especially when combined with UV exposure.
What are the main side effects of Khella?
Common side effects include nausea, dizziness, constipation, headache, and increased skin sensitivity to sunlight. Liver problems are a rare but serious side effect.
Does Khella interact with other medications?
Limited information is available on drug interactions, but caution is advised with medications that affect liver function due to khella's potential for liver toxicity.
Research Sources
- https://www.drugs.com/npp/khella.html – This source provides a general overview of khella, including its traditional uses, potential benefits, and a comprehensive list of known side effects and safety warnings. It highlights the lack of extensive human clinical trials for many of its purported benefits.
- https://publichealth.jmir.org/2024/1/e63808 – This article discusses the broader context of herbal medicine research. While not directly about khella, it underscores the challenges and importance of rigorous scientific validation for traditional remedies, which is relevant to the limited comprehensive studies on khella.
- https://pubmed.ncbi.nlm.nih.gov/33183658/ – This PubMed entry likely refers to a study on the effects of khella or its compounds. It contributes to the understanding of specific mechanisms or applications, such as its role in cholesterol management or hypoglycemic effects, though human data may be limited.
- https://pmc.ncbi.nlm.nih.gov/articles/PMC5825323/ – This PMC article focuses on the effectiveness of khellin, the active compound in khella, particularly in combination with UV therapy for treating vitiligo. It provides evidence for khellin's role as a photosensitizer and its clinical utility in repigmentation.
- https://www.webmd.com/vitamins/ai/ingredientmono-1034/khella – WebMD offers a consumer-friendly summary of khella, detailing its uses, potential effectiveness, side effects, and dosage considerations. It emphasizes the need for caution due to safety concerns, particularly liver issues and photosensitivity.
