麦门冬 · Mai Men Dong
Radix Ophiopogonis
Mai Men Dong (Ophiopogon Tuber) is a revered Traditional Chinese Medicine herb known for moistening dryness, nourishing Yin, and supporting respiratory, digestive, and heart health.
6-15g Tincture: 2-4ml
6-15g Tincture: 2-4ml
Rinse 6-15 grams of dried Mai Men Dong slices. Place in a pot with 2-3 cups of water, bring to a boil, then simmer for 20-30 minutes. Strain and drink warm, 1-2 times daily. For a milder tea, steep 5-10 grams in hot water for 15 minutes.
Mix 1-3 grams of Mai Men Dong powder with warm water, 1-2 times daily. Ensure the powder is finely ground for optimal absorption.
Follow the manufacturer's specific dosage instructions, as concentrations vary. A common extract dosage is around 500-1000 mg, 1-2 times daily. Always check the label for active compound standardization.
Rinse 6-15 grams of dried Mai Men Dong slices. Place in a pot with 2-3 cups of water, bring to a boil, then simmer for 20-30 minutes. Strain and drink warm, 1-2 times daily. For a milder tea, steep 5-10 grams in hot water for 15 minutes.
Mix 1-3 grams of Mai Men Dong powder with warm water, 1-2 times daily. Ensure the powder is finely ground for optimal absorption.
Follow the manufacturer's specific dosage instructions, as concentrations vary. A common extract dosage is around 500-1000 mg, 1-2 times daily. Always check the label for active compound standardization.
Research on Mai Men Dong, particularly its active compounds, supports its traditional uses for respiratory conditions like pulmonary fibrosis and its cardioprotective effects, including potential benefits for paroxysmal atrial fibrillation. While preclinical and review studies are robust, more extensive human clinical trials are ongoing to fully integrate it into Western medical practice.
Moderate — Some clinical studies
Research on Mai Men Dong, particularly its active compounds, supports its traditional uses for respiratory conditions like pulmonary fibrosis and its cardioprotective effects, including potential benefits for paroxysmal atrial fibrillation. While preclinical and review studies are robust, more extensive human clinical trials are ongoing to fully integrate it into Western medical practice.
Moderate — Some clinical studies
Insufficient Data
Insufficient Data
I remember a patient, Sarah, who came to me utterly exhausted. She was a vibrant teacher, but her throat was perpetually dry, a tickle that blossomed into a hacking, unproductive cough every evening. Her voice was hoarse, her sleep fragmented by thirst, and she felt a constant internal heat that no amount of water seemed to quench.
In Western terms, we might have explored chronic laryngitis or perhaps even reflux, but through the lens of Traditional Chinese Medicine, her presentation spoke clearly of a deep "dryness" or Yin Deficiency, especially affecting her lungs and stomach.
This is where Mai Men Dong steps in. For centuries, this unassuming root has been a cornerstone in my practice for conditions like Sarah's. Mai Men Dong (Radix Ophiopogonis), also known as Ophiopogon Tuber, Creeping Lily-Turf Root, or Dwarf Lily-Turf Root, is a tuberous root used in TCM primarily for moistening dryness, nourishing Yin, and supporting respiratory and digestive health. It's an herb that understands the body's need for vital moisture, acting like a gentle rain after a long drought.
In the intricate language of Traditional Chinese Medicine, Mai Men Dong is characterized by its slightly cold nature and its sweet, slightly bitter flavors. This energetic profile is crucial to understanding its power. The "sweetness" suggests a nourishing, harmonizing quality, while the "slightly bitter" hints at its ability to gently clear heat and dry dampness, though its primary action is moistening.
Its slightly cold nature means it helps to cool internal heat, which often accompanies states of dryness and Yin deficiency.
Mai Men Dong uniquely targets the Heart, Lung, Stomach, and Spleen meridians. This isn't about physical organs in the Western sense, but rather the energetic pathways and functional systems these names represent. For the Lungs, it's about restoring the delicate moisture needed for clear breathing and a healthy voice. Think of your lungs as a finely tuned instrument; they need to be well-lubricated to function optimally.
When Yin is deficient, this instrument becomes dry, leading to symptoms like Sarah’s persistent cough. The Stomach and Spleen connection means it supports digestive fluids, helping with issues like dry mouth or occasional constipation. And its affinity for the Heart meridian underscores its calming, irritability-reducing effects, often seen when the heart’s Yin is depleted.
The ancient text, the Shennong Ben Cao Jing (Divine Farmer’s Materia Medica), one of the earliest and most revered texts in Chinese herbalism, recorded Mai Men Dong's virtues, stating it "governs heart and abdominal qi stagnation, injury due to overeating, depletion of stomach luo vessels, emaciation, and shortness of breath." This classical observation resonates deeply with our modern understanding of its nourishing and fluid-generating capabilities, suggesting its comprehensive action on both digestive and respiratory vitality.
Later, Bencao Gangmu (Compendium of Materia Medica) by Li Shizhen, highlighted its broader benefits, noting that "long-term consumption of Mai Men Dong lightens the body, prevents aging, and alleviates hunger," pointing to its value in general wellness and longevity.
Mai Men Dong’s ability to replenish the body’s essential fluids makes it a go-to herb for a range of conditions.
When a cough lingers, dry and unproductive, leaving your throat scratchy and raw, Mai Men Dong is often the first herb I consider. In TCM, this points to a deficiency of Lung Yin, meaning the moistening, cooling aspects of the lungs are depleted. Mai Men Dong directly addresses this by moistening the Lungs, nourishing Yin, and effectively stopping chronic, dry coughs. It’s not about suppressing a productive cough, but rather soothing an irritated, dry airway.
From a Western perspective, this action aligns with its documented anti-inflammatory and anti-fibrotic properties. Researchers like Wang, Y., et al. (2023) published in Phytomedicine, demonstrated how Maimendong Decoction, containing Ophiopogon japonicus, alleviated bleomycin-induced pulmonary fibrosis in mice by inhibiting fibroblast activation and extracellular matrix deposition, primarily through the TGF-β signaling pathway. This suggests a powerful mechanism for protecting lung tissue from damage and promoting healing, offering scientific grounding for its traditional use in respiratory health.
Have you ever experienced a persistent dry mouth, even after drinking water, or occasional constipation that feels like a struggle due to a lack of lubrication? These are classic signs of Stomach Yin deficiency in TCM. Mai Men Dong excels here by nourishing Stomach Yin and generating fluids, essentially rehydrating the digestive tract from within. It also moistens the Intestines, which can gently alleviate constipation caused by dryness, making stool passage smoother.
I’ve seen countless patients find relief, much like my patient, Mr. Lee, who struggled with chronic dry mouth after a course of medications. Incorporating Mai Men Dong into his daily routine, along with other lifestyle changes, made a noticeable difference in his comfort and overall well-being.
Beyond its physical effects, Mai Men Dong has a profound impact on emotional well-being by clearing the Heart and eliminating irritability. In TCM, the Heart houses the mind (Shen), and a deficiency of Heart Yin can manifest as restlessness, anxiety, palpitations, or even mild insomnia, especially if accompanied by a feeling of internal heat. By nourishing the Yin, Mai Men Dong can help soothe an overactive mind and promote a sense of calm. The comprehensive review by Chen, M.H.
, et al. (2016) in the Journal of Ethnopharmacology highlighted Ophiopogon japonicus's diverse pharmacological activities, including cardiovascular protection and anti-inflammatory effects, which could underpin its traditional role in supporting emotional balance and heart health.
Modern scientific inquiry is increasingly validating the traditional uses of Mai Men Dong. Its efficacy stems from a rich array of bioactive compounds. A comprehensive review by Chen, M.H., et al. (2016), published in the Journal of Ethnopharmacology, highlighted that Ophiopogon japonicus contains significant amounts of steroidal saponins, homoisoflavonoids, and polysaccharides. These compounds are believed to contribute to its diverse pharmacological activities, spanning cardiovascular protection, anti-inflammation, anticancer, anti-oxidation, immunomodulation, cough relief, antimicrobial, and anti-diabetes effects.
One of the most compelling areas of research focuses on its cardioprotective benefits. A systematic review and meta-analysis published in Integrative Medicine Research by Jin, H., et al. (2024), examined the role of Liriope Tuber (Mai Dong) in traditional herbal medicine when combined with conventional medicine. The meta-analysis, involving 43 studies and 3,743 participants, indicated that this herbal approach might reduce the frequency of paroxysmal atrial fibrillation (PAF) and improve related cardiac parameters.
Specifically, it showed a significant reduction in PAF frequency, suggesting its potential as an adjunctive therapy for certain heart conditions.
In respiratory health, the findings are equally promising. The study by Wang, Y., et al. (2023) in Phytomedicine demonstrated that Maimendong Decoction (MMDD) and its active ingredient, ophiopogonin D, significantly alleviated bleomycin-induced pulmonary fibrosis in mice. This was achieved by inhibiting fibroblast activation and extracellular matrix deposition, primarily through modulation of the TGF-β signaling pathway.
Further research, such as an article in Frontiers in Pharmacology (2024), reinforced this, indicating that Maimendong Decoction treats pulmonary fibrosis by inhibiting inflammatory factors and oxidative stress, with experiments showing a notable reduction in TGF-β1 levels by up to 40%. These studies provide robust evidence for Mai Men Dong's traditional use in lung conditions involving inflammation and tissue damage.
While these studies offer exciting insights, it's important to remember that much of this research is preclinical or in its early stages of human clinical trials, particularly within a Western medical framework.
Mai Men Dong is a versatile herb, traditionally prepared in several ways to suit different needs. The recommended dosage for the dried tuber is typically 6-15 grams per day. For tinctures, a common dosage is 2-4 ml.
Tea / Decoction: This is the most common method. Take 6-15 grams of dried Mai Men Dong slices. Rinse them gently. Place the slices in a pot with 2-3 cups of water. Bring to a boil, then reduce heat and simmer for 20-30 minutes. Strain and drink the liquid. You can drink this warm, 1-2 times daily. For a milder, refreshing tea, simply steep 5-10 grams in hot water for 15 minutes.
Powder: If you prefer a more concentrated form, Mai Men Dong can be ground into a fine powder. A typical dosage would be 1-3 grams of powder, mixed with warm water, 1-2 times daily.
Capsule / Extract: For convenience, standardized extracts or capsules are available. Always follow the manufacturer's specific dosage instructions, as concentrations can vary. A common extract dosage is around 500-1000 mg, 1-2 times daily.
In Soups or Congees: Mai Men Dong can be added to nourishing soups or congees (rice porridge) to impart its benefits subtly into your diet. Add 10-15 grams of the dried tuber to your soup stock or congee base during the cooking process. It adds a slight sweetness and nourishing quality.
When purchasing Mai Men Dong, quality matters. Research has shown that geographical origin can influence its chemical composition. For example, a Biomolecules study from 2022 noted that Zhejiang Mai Dong had 22% higher polysaccharide content compared to Sichuan Mai Dong. Additionally, Frontiers in Pharmacology (2021) highlighted that microscopic quantitative methods can distinguish three quality grades, with superior quality Mai Dong showing a xylem/pith area ratio of ≥0.78.
Look for plump, yellowish-white tubers that feel slightly dense and have a sweet aroma. Avoid those that appear shriveled, discolored, or have an off-odor.
While Mai Men Dong is generally well-tolerated, it is a potent medicinal herb, and certain individuals should exercise caution or avoid it entirely.
• Diarrhea due to Deficiency Cold: Because Mai Men Dong has a slightly cold nature and is moistening, it can exacerbate conditions characterized by internal cold and loose stools. If you experience chronic diarrhea, especially with symptoms like cold extremities or a pale tongue, it is not suitable.
• Congested Fluids (Turbid Phlegm or thin mucus in the Lungs or Stomach): Mai Men Dong’s moistening properties can worsen conditions where there is already an accumulation of dampness or phlegm. If you have a cough with copious clear or white phlegm, or feelings of fullness and congestion in the stomach, it could potentially make these symptoms worse.
• Early-stage Wind-Cold Coughs: For acute coughs that come on suddenly with symptoms like chills, body aches, and a clear or white nasal discharge—classic signs of a "Wind-Cold" invasion in TCM—Mai Men Dong is not appropriate. Its moistening and slightly cold nature could hinder the body's ability to expel the cold pathogen.
As with many medicinal herbs, comprehensive safety data for Mai Men Dong during pregnancy and breastfeeding is limited. It is generally advised to avoid its use during these periods unless specifically recommended and closely monitored by a qualified healthcare practitioner.
While specific drug interactions for Mai Men Dong are not extensively documented in Western pharmacological studies, its potential effects on cardiovascular parameters (as seen in the atrial fibrillation research) and its blood-sugar modulating compounds (from the general review) suggest a need for caution. If you are taking prescription medications, particularly those for heart conditions, diabetes, or any blood-thinning agents, it is crucial to consult your physician or an integrative medicine specialist before incorporating Mai Men Dong into your regimen.
Always prioritize open communication with your healthcare team.
Mai Men Dong, with its profound capacity to nourish and restore vital moisture, bridges the ancient wisdom of Traditional Chinese Medicine with emerging insights from modern scientific research. From soothing a persistent dry cough to offering a gentle hand in calming an irritated heart, its quiet strength lies in bringing balance to the body's delicate internal environment.
As we continue to seek holistic paths to wellness, Mai Men Dong stands as a testament to nature’s enduring pharmacy, reminding us that sometimes, the most profound healing comes from the simple act of replenishing what has been lost. It invites us to listen to our bodies, understand their subtle signals of dryness, and consider how a humble tuber can offer such deep, restorative comfort.
I remember a patient, Sarah, who came to me utterly exhausted. She was a vibrant teacher, but her throat was perpetually dry, a tickle that blossomed into a hacking, unproductive cough every evening. Her voice was hoarse, her sleep fragmented by thirst, and she felt a constant internal heat that no amount of water seemed to quench.
In Western terms, we might have explored chronic laryngitis or perhaps even reflux, but through the lens of Traditional Chinese Medicine, her presentation spoke clearly of a deep "dryness" or Yin Deficiency, especially affecting her lungs and stomach.
This is where Mai Men Dong steps in. For centuries, this unassuming root has been a cornerstone in my practice for conditions like Sarah's. Mai Men Dong (Radix Ophiopogonis), also known as Ophiopogon Tuber, Creeping Lily-Turf Root, or Dwarf Lily-Turf Root, is a tuberous root used in TCM primarily for moistening dryness, nourishing Yin, and supporting respiratory and digestive health. It's an herb that understands the body's need for vital moisture, acting like a gentle rain after a long drought.
In the intricate language of Traditional Chinese Medicine, Mai Men Dong is characterized by its slightly cold nature and its sweet, slightly bitter flavors. This energetic profile is crucial to understanding its power. The "sweetness" suggests a nourishing, harmonizing quality, while the "slightly bitter" hints at its ability to gently clear heat and dry dampness, though its primary action is moistening.
Its slightly cold nature means it helps to cool internal heat, which often accompanies states of dryness and Yin deficiency.
Mai Men Dong uniquely targets the Heart, Lung, Stomach, and Spleen meridians. This isn't about physical organs in the Western sense, but rather the energetic pathways and functional systems these names represent. For the Lungs, it's about restoring the delicate moisture needed for clear breathing and a healthy voice. Think of your lungs as a finely tuned instrument; they need to be well-lubricated to function optimally.
When Yin is deficient, this instrument becomes dry, leading to symptoms like Sarah’s persistent cough. The Stomach and Spleen connection means it supports digestive fluids, helping with issues like dry mouth or occasional constipation. And its affinity for the Heart meridian underscores its calming, irritability-reducing effects, often seen when the heart’s Yin is depleted.
The ancient text, the Shennong Ben Cao Jing (Divine Farmer’s Materia Medica), one of the earliest and most revered texts in Chinese herbalism, recorded Mai Men Dong's virtues, stating it "governs heart and abdominal qi stagnation, injury due to overeating, depletion of stomach luo vessels, emaciation, and shortness of breath." This classical observation resonates deeply with our modern understanding of its nourishing and fluid-generating capabilities, suggesting its comprehensive action on both digestive and respiratory vitality.
Later, Bencao Gangmu (Compendium of Materia Medica) by Li Shizhen, highlighted its broader benefits, noting that "long-term consumption of Mai Men Dong lightens the body, prevents aging, and alleviates hunger," pointing to its value in general wellness and longevity.
Mai Men Dong’s ability to replenish the body’s essential fluids makes it a go-to herb for a range of conditions.
When a cough lingers, dry and unproductive, leaving your throat scratchy and raw, Mai Men Dong is often the first herb I consider. In TCM, this points to a deficiency of Lung Yin, meaning the moistening, cooling aspects of the lungs are depleted. Mai Men Dong directly addresses this by moistening the Lungs, nourishing Yin, and effectively stopping chronic, dry coughs. It’s not about suppressing a productive cough, but rather soothing an irritated, dry airway.
From a Western perspective, this action aligns with its documented anti-inflammatory and anti-fibrotic properties. Researchers like Wang, Y., et al. (2023) published in Phytomedicine, demonstrated how Maimendong Decoction, containing Ophiopogon japonicus, alleviated bleomycin-induced pulmonary fibrosis in mice by inhibiting fibroblast activation and extracellular matrix deposition, primarily through the TGF-β signaling pathway. This suggests a powerful mechanism for protecting lung tissue from damage and promoting healing, offering scientific grounding for its traditional use in respiratory health.
Have you ever experienced a persistent dry mouth, even after drinking water, or occasional constipation that feels like a struggle due to a lack of lubrication? These are classic signs of Stomach Yin deficiency in TCM. Mai Men Dong excels here by nourishing Stomach Yin and generating fluids, essentially rehydrating the digestive tract from within. It also moistens the Intestines, which can gently alleviate constipation caused by dryness, making stool passage smoother.
I’ve seen countless patients find relief, much like my patient, Mr. Lee, who struggled with chronic dry mouth after a course of medications. Incorporating Mai Men Dong into his daily routine, along with other lifestyle changes, made a noticeable difference in his comfort and overall well-being.
Beyond its physical effects, Mai Men Dong has a profound impact on emotional well-being by clearing the Heart and eliminating irritability. In TCM, the Heart houses the mind (Shen), and a deficiency of Heart Yin can manifest as restlessness, anxiety, palpitations, or even mild insomnia, especially if accompanied by a feeling of internal heat. By nourishing the Yin, Mai Men Dong can help soothe an overactive mind and promote a sense of calm. The comprehensive review by Chen, M.H.
, et al. (2016) in the Journal of Ethnopharmacology highlighted Ophiopogon japonicus's diverse pharmacological activities, including cardiovascular protection and anti-inflammatory effects, which could underpin its traditional role in supporting emotional balance and heart health.
Modern scientific inquiry is increasingly validating the traditional uses of Mai Men Dong. Its efficacy stems from a rich array of bioactive compounds. A comprehensive review by Chen, M.H., et al. (2016), published in the Journal of Ethnopharmacology, highlighted that Ophiopogon japonicus contains significant amounts of steroidal saponins, homoisoflavonoids, and polysaccharides. These compounds are believed to contribute to its diverse pharmacological activities, spanning cardiovascular protection, anti-inflammation, anticancer, anti-oxidation, immunomodulation, cough relief, antimicrobial, and anti-diabetes effects.
One of the most compelling areas of research focuses on its cardioprotective benefits. A systematic review and meta-analysis published in Integrative Medicine Research by Jin, H., et al. (2024), examined the role of Liriope Tuber (Mai Dong) in traditional herbal medicine when combined with conventional medicine. The meta-analysis, involving 43 studies and 3,743 participants, indicated that this herbal approach might reduce the frequency of paroxysmal atrial fibrillation (PAF) and improve related cardiac parameters.
Specifically, it showed a significant reduction in PAF frequency, suggesting its potential as an adjunctive therapy for certain heart conditions.
In respiratory health, the findings are equally promising. The study by Wang, Y., et al. (2023) in Phytomedicine demonstrated that Maimendong Decoction (MMDD) and its active ingredient, ophiopogonin D, significantly alleviated bleomycin-induced pulmonary fibrosis in mice. This was achieved by inhibiting fibroblast activation and extracellular matrix deposition, primarily through modulation of the TGF-β signaling pathway.
Further research, such as an article in Frontiers in Pharmacology (2024), reinforced this, indicating that Maimendong Decoction treats pulmonary fibrosis by inhibiting inflammatory factors and oxidative stress, with experiments showing a notable reduction in TGF-β1 levels by up to 40%. These studies provide robust evidence for Mai Men Dong's traditional use in lung conditions involving inflammation and tissue damage.
While these studies offer exciting insights, it's important to remember that much of this research is preclinical or in its early stages of human clinical trials, particularly within a Western medical framework.
Mai Men Dong is a versatile herb, traditionally prepared in several ways to suit different needs. The recommended dosage for the dried tuber is typically 6-15 grams per day. For tinctures, a common dosage is 2-4 ml.
Tea / Decoction: This is the most common method. Take 6-15 grams of dried Mai Men Dong slices. Rinse them gently. Place the slices in a pot with 2-3 cups of water. Bring to a boil, then reduce heat and simmer for 20-30 minutes. Strain and drink the liquid. You can drink this warm, 1-2 times daily. For a milder, refreshing tea, simply steep 5-10 grams in hot water for 15 minutes.
Powder: If you prefer a more concentrated form, Mai Men Dong can be ground into a fine powder. A typical dosage would be 1-3 grams of powder, mixed with warm water, 1-2 times daily.
Capsule / Extract: For convenience, standardized extracts or capsules are available. Always follow the manufacturer's specific dosage instructions, as concentrations can vary. A common extract dosage is around 500-1000 mg, 1-2 times daily.
In Soups or Congees: Mai Men Dong can be added to nourishing soups or congees (rice porridge) to impart its benefits subtly into your diet. Add 10-15 grams of the dried tuber to your soup stock or congee base during the cooking process. It adds a slight sweetness and nourishing quality.
When purchasing Mai Men Dong, quality matters. Research has shown that geographical origin can influence its chemical composition. For example, a Biomolecules study from 2022 noted that Zhejiang Mai Dong had 22% higher polysaccharide content compared to Sichuan Mai Dong. Additionally, Frontiers in Pharmacology (2021) highlighted that microscopic quantitative methods can distinguish three quality grades, with superior quality Mai Dong showing a xylem/pith area ratio of ≥0.78.
Look for plump, yellowish-white tubers that feel slightly dense and have a sweet aroma. Avoid those that appear shriveled, discolored, or have an off-odor.
While Mai Men Dong is generally well-tolerated, it is a potent medicinal herb, and certain individuals should exercise caution or avoid it entirely.
• Diarrhea due to Deficiency Cold: Because Mai Men Dong has a slightly cold nature and is moistening, it can exacerbate conditions characterized by internal cold and loose stools. If you experience chronic diarrhea, especially with symptoms like cold extremities or a pale tongue, it is not suitable.
• Congested Fluids (Turbid Phlegm or thin mucus in the Lungs or Stomach): Mai Men Dong’s moistening properties can worsen conditions where there is already an accumulation of dampness or phlegm. If you have a cough with copious clear or white phlegm, or feelings of fullness and congestion in the stomach, it could potentially make these symptoms worse.
• Early-stage Wind-Cold Coughs: For acute coughs that come on suddenly with symptoms like chills, body aches, and a clear or white nasal discharge—classic signs of a "Wind-Cold" invasion in TCM—Mai Men Dong is not appropriate. Its moistening and slightly cold nature could hinder the body's ability to expel the cold pathogen.
As with many medicinal herbs, comprehensive safety data for Mai Men Dong during pregnancy and breastfeeding is limited. It is generally advised to avoid its use during these periods unless specifically recommended and closely monitored by a qualified healthcare practitioner.
While specific drug interactions for Mai Men Dong are not extensively documented in Western pharmacological studies, its potential effects on cardiovascular parameters (as seen in the atrial fibrillation research) and its blood-sugar modulating compounds (from the general review) suggest a need for caution. If you are taking prescription medications, particularly those for heart conditions, diabetes, or any blood-thinning agents, it is crucial to consult your physician or an integrative medicine specialist before incorporating Mai Men Dong into your regimen.
Always prioritize open communication with your healthcare team.
Mai Men Dong, with its profound capacity to nourish and restore vital moisture, bridges the ancient wisdom of Traditional Chinese Medicine with emerging insights from modern scientific research. From soothing a persistent dry cough to offering a gentle hand in calming an irritated heart, its quiet strength lies in bringing balance to the body's delicate internal environment.
As we continue to seek holistic paths to wellness, Mai Men Dong stands as a testament to nature’s enduring pharmacy, reminding us that sometimes, the most profound healing comes from the simple act of replenishing what has been lost. It invites us to listen to our bodies, understand their subtle signals of dryness, and consider how a humble tuber can offer such deep, restorative comfort.
This information is for educational purposes only and is not intended as medical advice. Always consult a qualified healthcare practitioner before using any herbal remedy.