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Wild lettuce is often used in the treatment of acute insomnia, restlessness and tension

Wild Lettuce

Lactuca virosa Asteraceaea

Wild lettuce is a common European weed that has been used for centuries for acute insomnia and anxiety. As one of the great acrid bitters, wild lettuce reduces heat and tension. It may be applied for spasmodic conditions in the musculoskeletal and respiratory systems.

  • How does it feel?

    Wild lettuce is an acrid, bitter cooling medicine that offers a grounding and relaxing effect upon the mind and body. Hypnotic and sedative herbs like wild lettuce can support the health status of all body systems as they allow for deep relaxation and relief from nervous tension.

    Wild lettuce lives up to its common name ‘bitter lettuce’ with a sharp bitterness that sits on the sides of the tongue. There is also a notable mild earthy taste.

  • What can I use it for?

    Whilst wild lettuce is a commonly foraged salad green in Europe and some parts of UK it is not so much of an entry level plant for home herbalism. It is often used by herbalists for its antispasmodic and sedative actions. However, there are reports of people experiencing side effects from its use. This was from having very high doses, which highlights why it is important to respect and reference traditional use and knowledge. You can learn more about this in the safety section of this article and we have listed doses here.

    As a foraged edible, it has a potent bitter flavour so is often recommended by foragers to be used at a lower ratio as the flavour may be overpowering for some. Most would say wild lettuce has a  late summer harvest. Or is harvested late summer?

    In medicinal doses, wild lettuce may be used to help with short-term sleep disturbances. It is a sedative and hypnotic so it is sometimes used for insomnia and to help one relax into deep and fulfilling sleep.

    As an antispasmodic agent, wild lettuce is also used to support with persistent coughs that follow on from acute viral infections such as a cold. The best application of wild lettuce for this purpose is for the dryer, spasmodic type of coughs. Herbalists don’t often recommend suppressing the cough reflex for productive coughs due to the understanding of its physiological purpose to clear the lungs. See ‘What practitioners say’ for more information on this and how wild lettuce is used by herbalists.

    It is best to seek medical advice if a cough persists for longer than 3- 4 weeks as persistent coughs can sometimes indicate a more serious health condition.

  • Into the heart of Wild Lettuce

    In the understanding of western herbalism wild lettuce is moderately cooling and slightly moist. Put simply, moist and cooling herbs are used to treat hot, inflammatory conditions that have dry tendencies. These are preferred over dry cooling (e.g. raspberry leaves, plantain), or dry warming (nettle, rosemary) herbs for example; those that have more astringency which may be counterproductive in the treatment of these type of conditions (2).

    In traditional Chinese medicine (TCM) plants with an acrid flavour are used to treat wind and chill. In TCM these are conditions that are equivalent to constriction. The appropriate energetic manifestation of such illness may be seen as tension, muscle spasms and chills that are not easily calmed. The mind and nerves are deeply affected by this tissue state and symptoms of unease in the mind may include anxiety, panic and nervousness. Such tissue state in the TCM understanding is described as an excess of wind and chill (2).

    The energetic picture of wild lettuce as described above is well reflected in its traditional and modern applications in treatment of tensions. Wild lettuce can be applied for tensions in the mind (nervousness, hyperactivity and insomnia) and in the body (spasmodic conditions in the musculoskeletal and respiratory system). Its effects are subtle, and it is often combined with other grounding herbs such as skullcap and valerian.

  • Traditional uses

    In the mid 1700’s wild lettuce was well known as a painkiller and sedative in European folk tradition.

    The plant-protecting latex was traditionally extracted into a black resin leading to it being called ‘opium lettuce’. Herbalists called this dried latex ‘lactucarium’ which is easy to store and administer.

    Later, in the 19th century, the juice or ‘lactucarium’, was more widely used for the same effects. There was also reference for use in kidney disorders, for ameliorating painful uterine contractions linked to menstruation, and for generalised oedema and jaundice, likely due to its diuretic and detoxifying effects.

    Wild lettuce was at the heart of some very early research due to its opiate content. Mrs Greive states that an early practitioner in research of plant medicines, Dr Collins reported that ‘twenty-three out of twenty-four cases of dropsy were cured by taking doses of 18 grains to 3 drachms of extract in twenty-four hours’ (1).

  • Traditional actions

    • Analgesic
    • Anti-inflammatory
    • Antitussive
    • Antipyretic
    • Bitter
    • Diaphoretic
    • Diuretic
    • Expectorant
    • Hepatic
    • Nervine
    • Sedative
  • What practitioners say

    Nervous system: As a sedative and hypnotic, wild lettuce is primarily used in the treatment of acute sleep disturbances and insomnia. This may be applied to help moderate tensions and anxiety syndromes in the short term. Sedative herbs like wild lettuce are also indicated to support those weaning off conventional sedative medications (5).

    Another potential indication for wild lettuce is hyperactivity and over-excitability. The sedative effects of this herb will also be supportive for those suffering from acute anxiety and restlessness.

    A herbalist will use sedatives only intermittently or for short periods. For example, they may be applied to support patients during acute phases of insomnia and anxiety. This is because they work to treat the symptom of a problem rather than the root cause and for long-term healing to happen one would need more than just a sedative.

    For chronic conditions, a medical herbalist would make a formulation which would aim to resolve the issue on a deeper level. A herbalist understands that the root cause of disease will often be unique to the patient and will require a personalised approach to address the problem. Whilst home herbalism is a powerful and useful skill, consulting a learned herbalist will always be best for chronic and complex conditions.

    Musculoskeletal system: Wild lettuce may be used where there are tensions or spasmodic states throughout the body. It is specifically antispasmodic and anti-rheumatic, and so it may therefore be applied to work upon smooth and striated muscle tensions. This is mostly taken as an internal medicine to work on the tissue state systemically rather than as a topical preparation, although historically it was applied in both internal and external forms (3).

    Respiratory system: Wild lettuce’s excellent antispasmodic properties may be applied in the holistic treatment of spasmodic coughs. It has long been used as an anti-tussive (an agent that reduces coughing).

    This action may be used in the circumstances of a nervous cough or by a practitioner who may prescribe this plant where relentless coughing is caused by a tumour for example. Another typical indication for antitussives would be a non-productive, severe or persistent cough that is stubborn against treatment with expectorants (5).

    Many herbalists understand that reducing the cough reflex may in fact be counterproductive for example where irritants or mucous congestion is the cause. This is because the cough reflex allows for the mobilisation and expulsion of congestion and therefore relief. Herbalists understand that reducing this reflex may reduce the necessary cleansing of the lungs (5).

    Reproductive system: Wild lettuce is an anaphrodisiac, which means that it reduces sexual desire. It may also be applied for its antispasmodic properties to assist in menstrual cramps.

  • Research

    There is little available modern research on wild lettuce, particularly clinical trials and human studies. Animal studies, particularly those using isolated compounds are not only unethical but they are also problematic due to their lacking in context against the holistic understanding of human pathophysiology. This type of research does not reflect the complexities of the patient’s pathophysiology, nor the plant phytochemically.

    Animal studies are not condoned by herbal reality, however for the purpose of including research from which some understanding of therapeutic actions can be confirmed, animal studies have been included herein.

    Analgesic and sedative

    A study was carried out in which three active compounds, found in wild lettuce – lactucin and its derivatives lactucopicrin and 11β,13-dihydrolactucin were investigated for their sedative and analgesic effects, using in vivo methods.

    The compounds showed similar analgesic effects at doses of 15 and 30 mg in the hot plate test in a similar capacity to ibuprofen. Of the three compounds, lactucopicrin appeared to be the most potent in analgesic outcomes. Lactucin and lactucopicrin, but not 11β,13-dihydrolactucin, also showed positive sedative properties (8).

    Anti-inflammatory

    A study was carried out to evaluate the anti-inflammatory effects of the aqueous extracts of asthma plant (Euphorbia hirta) and wild lettuce. The study combined data from in vivo and in vitro methods. The former was to induce Albumin and histamine inflammation in mice as well as xylene induced ear oedema.

    A number of variants in combination of the two plants were given, all showing a significant reduction of paw inflammation in mice compared to the control in the albumin and histamine induced inflammatory test. The study concludes a positive anti-inflammatory potential for the plant extracts of asthma plant and wild lettuce both in vivo and in vitro (7).

    Lactucarium

    Lactucarium is a diuretic, laxative and sedative agent. It is well-referenced for use as an anti-tussive and to relieve dyspnoea. Due to its antispasmodic effects, it also decreases gastrointestinal inflammation and spasmolysis as well as uterine contractions. It has anticonvulsant and hypnotic effects as well. Additionally, lactucarium contains traces of hyoscyamine, an alkaloid found in henbane and other nightshade plants. This is thought to be the likely explanation for its sedative effects (6).

  • Did you know?

    The latex (or milky sap) of wild lettuce was once sold as ‘lettuce opium’ or lactucarium, as it was called in the official pharmacopoeias of the day. It is said to contain nano-particles of opium, however not in amounts that would qualify it as a major opiate agent. Herbal medicines often contain hundreds of active compounds that work synergistically to create their effect, as is the case with wild lettuce.

Additional information

  • Safety

    There are reports of side effects for this plant. A paper was published in 2009 describing 8 patients who were admitted to the same hospital who had apparently ingested wild lettuce as fresh herb potentially in large quantities. It was also speculated that the herb had been harvested before the usual time for harvesting. Usually, wild lettuce is harvested in late summer. In this case, it is suggested that harvesting took place in May (6).

    The paper suggests that this was a case of overdose. It is important to follow the recommended dosage advice to avoid adverse reactions. The side effects from overdose included mydriasis, photophobia, dizziness, diaphoresis, auditory hallucination, and cardiovascular and respiratory difficulties caused by dysrhythmia (6).

    It is important to note the reports are out of context with normal prescribing levels, and the people had a very high dose. Given the compounds in wild lettuce, it is not surprising people had unwanted effects. This highlights the importance of referring to credible herbal texts which highlight how herbalists use the plant, in order to make sure it is used safely. Better yet, see a herbalist.

    Wild lettuce should be avoided during pregnancy and lactation.

  • Interactions

    Wild lettuce may enhance the effects of sedative medications. It is best to avoid taking wild lettuce if you are using any medications that may induce sedation.

  • Contraindications

    Wild lettuce should be avoided by those who have a known sensitivity or allergy to plants in the Asteraceae (daisy) family

  • Preparation

    • Tincture
    • Lactucarium (a plastic-like solid brown substance made up of the dried latex/milky sap that is exuded from the plant when cut)
    • Dried leaf (less often)
    • Fresh i.e. mixed into a foraged salad
  • Dosage

    Tincture (1:1 in 25%): Tincture dosage is recommended at between 0.5ml-4ml

    Infusion: Infuse 1- 2 teaspoons of dried herb into a mug of boiling water and infuse for up to 15 minutes. Strain and drink up to three times a day.

    Dried or raw plant: 0.5-4g a day

    Lactucarium: The US pharmacopoeia recommends a dosage of 2ml lactucarium tincture three times a day (4).

  • Plant parts used

    • Whole aerial parts
    • Leaf
  • Constituents

    • Sesquiterpene lactones – lactucin
    • Coumarins- ci-chorin and aesculin
    • Acids
    • Alkaloids- hyoscyamine
    • Flavanoids- querceti
    • Terpenoid bitters
    • Resin
    • N- methyl- β- phenethylamin (3, 6)
  • Habitat

    The native range of this species is Madeira, Europe and NW. Africa. It grows primarily in the temperate biome. Wild lettuce is widespread across much of central and southern Europe. It can be found locally in the South-east/ East of England. It is seldom found across the rest of the United Kingdom. Wild lettuce grows almost anywhere with good sunlight. It may be found growing between paving slabs, gaps in walls, flower beds and especially freshly disturbed soil around field edges.

  • Sustainability

    The IUCN Red List of Threatened Plants has assessed the population trends of this plant across Europe and pan Africa. It is currently classed as ‘Least concern’ under the red list database. This means that the population of this species is stable and under no specific threat of extinction (9).

    Habitat loss and over harvesting from the wild are two of the biggest threats faced by medicinal plant species. There are an increasing number of well-known herbal medicines at risk of extinction. We must therefore ensure that we source our medicines with sustainability in mind.

    The herb supplement industry is growing at a rapid rate and until recent years much of the medicinal plant produced in global trade was of unknown origin. There are some very real and urgent issues surrounding sustainability in the herb industry. These include environmental factors that affect the medicinal viability of herbs, the safety of the habitats that they are taken from, as well as the welfare of workers in the trade.

    The botanical supply chain efforts for improved visibility (transparency and traceability) into verifiably sustainable production sites around the world is now certificated through the emergence of credible international voluntary sustainability standards (VSS). Read our article on sustainable sourcing of herbs to learn more about what to look for and questions to ask suppliers about sustainability.

  • Quality control

    The milky sap that is produced by this plant which holds much of its medicinal compounds and is not viable as a medicine in powdered form. Most often this plant is made as whole plant or lactucarium tincture. It is only slightly soluble in boiling water, therefore an infusion is also a less viable option for using this plant medicinally (1).

    It is recommended to harvest this plant in the second year when it exudes more of the white latex for a more potent medicine.

    Herbal Medicines are often extremely safe to take, however it is important to supply herbal medicines from a reputed supplier. Sometimes herbs bought from unreputable sources are contaminated, adulterated or substituted with incorrect plant matter.

    Some important markers for quality to look for would be to look for certified organic labelling, ensuring that the correct scientific / botanical name is used and that suppliers can provide information about the source of ingredients used in the product. A supplier should be able to tell you where the herbs have come from. There is more space for contamination and adulteration where the supply chain is unknown.

  • How to grow

    Wild lettuce grows in the wild as a weed in many cooler parts of Europe. It is easy to grow and will spread each season when it goes to seed.

    • It is best to sow seeds in early spring or fall, in pots outdoors or directly in beds outdoors. Sprinkle soil on the seed and tamp securely, then keep cool and evenly moist until germination.
    • Germination should occur within 10 to 20 days, it can be longer in colder conditions.
    • In most cases a spacing of around 30cm between plants should be fine, but you may want to increase that a bit if the soil is rich in nutrients, producing larger leaves.
    • The plant needs very little care and will grow happily in well-drained sandy soils in a sunny position.
    • The leaves are edible and can be added to a salad (some may disagree because of the bitter flavour). However if it is the milky sap you are growing it for, leave it for the first year and harvest it when it has started to send up its flowering spikes in year two.
  • References

    1. botanical.com. (n.d.). A Modern Herbal | Lettuce, Wild. [online] Available at: https://www.botanical.com/botanical/mgmh/l/lettuc17.html [Accessed 7 Dec. 2022].
    2. M. 2004. The Practice of Traditional Western Herbalism: Basic Organs and Systems. North Atlantic Books,U.S.
    3. Menzies-Trull, C. (2013). Herbal medicine keys to physiomedicalism including pharmacopoeia. Newcastle: Faculty Of Physiomedical Herbal Medicine (Fphm).
    4. Hoffman, D. (2003). Medical Herbalism: The Science Principles and Practices Of Herbal Medicine. Hardback (1st Edition). Independently published
    5. Bone, K. and Mills, S. (2013). Principles and practice of phytotherapy modern herbal medicine. 2nd ed. Edinburgh Churchill Livingstone, Elsevier.
    6. Besharat, S., Besharat, M. and Jabbari, A. (2009). Wild lettuce (Lactuca virosa) toxicity. Case Reports, 2009(apr23 1), pp.bcr0620080134–bcr0620080134. doi:10.1136/bcr.06.2008.0134.
    7. Uwaya, D., Okakwu, R. and Omozuwa, O. (2021). In-Vivo and In-Vitro Anti-Inflammatory Activities of the Aqueous Extract of Di-Herbal Formulation (Euphorbia hirta and lactuca virosa). Journal of Applied Sciences and Environmental Management, 24(11), pp.1979–1985. doi:10.4314/jasem.v24i11.19.
    8. Wesołowska, A., Nikiforuk, A., Michalska, K., Kisiel, W. and Chojnacka-Wójcik, E. (2006). Analgesic and sedative activities of lactucin and some lactucin-like guaianolides in mice. Journal of Ethnopharmacology, 107(2), pp.254–258. doi:10.1016/j.jep.2006.03.003.
    9. Ouedraogo, L. (2008). IUCN Red List of Threatened Species: Lactuca virosa. [online] IUCN Red List of Threatened Species. Available at: https://www.iucnredlist.org/species/164487/5889689#habitat-ecology [Accessed 8 Dec. 2022].
Aromatic
An ‘aromatic’ remedy, high in volatile essential oils, was most often associated with calming and sometimes ‘warming’ the digestion. Most kitchen spices and herbs have this quality: they were used both as flavouring and to ease the digestion of sometimes challenging pre-industrial foods. Many aromatics are classed as ‘carminatives’ and are used to reduce colic, bloating and agitated digestion. They also often feature in respiratory remedies for colds, chest and other airway infections. They are also classic calming inhalants and massage oils, and are the basis of aromatherapy for their mental benefits.
Astringent taste
The puckering taste you get with many plants (the most familiar is black tea after being stewed too long, or some red wines) is produced by complex polyphenols such as tannins. Tannins are used in concentrated form (eg from oak bark) to make leather from animal skins. The process of ‘tanning’ involves the coagulation of relatively fluid proteins in living tissues into tight clotted fibres (similar to the process of boiling an egg). Tannins in effect turn exposed surfaces on the body into leather. In the case of the lining of mouth and upper digestive tract this is only temporary as new mucosa are replenished, but in the meantime can calm inflamed or irritated surfaces. In the case of open wounds tannins can be a life-saver – when strong (as in the bark of broadleaved trees) they can seal a damaged surface. One group of tannins, the reddish-brown ‘condensed tannins’ are procyanidins, which can reduce inflammation and oxidative damage.
Bitter
Bitters are a very complex group of phytochemicals that stimulate the bitter receptors in the mouth. They were some of the most valuable remedies in ancient medicine. They were experienced as stimulating appetite and switching on a wide range of key digestive functions, including increasing bile clearance from the liver (as bile is a key factor in bowel health this can be translated into improving bowel functions and the microbiome). Many of these reputations are being supported by new research on the role of bitter receptors in the mouth and elsewhere round the body. Bitters were also seen as ‘cooling’ reducing the intensity of some fevers and inflammatory diseases.
Blue-purple colouring
Any fruits with a blue-purple colouring contain high levels of the polyphenols known as anthocyanins. These work 1) on the walls of small blood vessels, helping to maintain capillary structure to reduce a key stage in inflammation, and improving the microcirculation to the tissues; 2) to improve retinal function and vision; 3) to support connective tissue repair around the body.
Cooling
Traditional ‘cold’ or cooling’ remedies often contain bitter phytonutrients such a iridoids (gentian), sesiquterpenes (chamomile), anthraquinones (rhubarb root), mucilages (marshmallow), some alkaloids and flavonoids. They tend to influence the digestive system, liver and kidneys. Cooling herbs do just that; they diffuse, drain and clear heat from areas of inflammation, redness and irritation. Sweet, bitter and astringent herbs tend to be cooling.
Hot
Traditional ‘hot’ or ‘heating’ remedies, often containing spice ingredients like capsaicin, the gingerols (ginger), piperine (black or long pepper), curcumin (turmeric) or the sulfurous isothiocyanates from mustard, horseradich or wasabi, generate warmth when taken. In modern times this might translate as thermogenic and circulatory stimulant effects. There is evidence of improved tissue blood flow with such remedies: this would lead to a reduction in build-up of metabolites and tissue damage. Heating remedies were used to counter the impact of cold, reducing any symptoms made worse in the cold. .
Mucilaginous
Mucilages are complex carbohydrate based plant constituents with a slimy or ‘unctuous’ feel especially when chewed or macerated in water. Their effect is due simply to their physical coating exposed surfaces. From prehistory they were most often used as wound remedies for their soothing and healing effects on damaged tissues. Nowadays they are used more for these effects on the digestive lining, from the throat to the stomach, where they can relieve irritation and inflammation such as pharyngitis and gastritis. Some of the prominent mucilaginous remedies like slippery elm, aloe vera and the seaweeds can be used as physical buffers to reduce the harm and pain caused by reflux of excess stomach acid. Mucilages are also widely used to reduce dry coughing. Here the effect seems to be by reflex through embryonic nerve connections: reduced signals from the upper digestive wall appear to translate as reduced activity of airway muscles and increased activity of airway mucus cells. Some seed mucilages, such as in psyllium seed, flaxseed (linseed) or guar bean survive digestion to provide bulking laxative effects in the bowel. These can also reduce rate of absorption of sugar and cholesterol. .
New-mown hay aroma
The familiar country odour of haymaking, of drying grass and other plants, is largely produced by coumarins (originally isolated from tonka beans – in French coumarou) and widely used in perfumery. They are chemically categorised as benzopyrone lactones and are important phytochemicals, with strong antioxidant activity in the laboratory and likely effects in modulating inflammation. They were most often associated with the calming effect linked to their use in stuffing mattresses and pillows and plants, high In coumarins were commonly used for these properties.
Resinous
Resins are most familiar as tacky discharges from pine trees (and as the substance in amber, and rosin for violin bows). They were most valued however as the basis of ancient commodities like frankincense and myrrh (two of the three gifts of the Three Wise Men to the baby Jesus) and getting access to their source was one benefit to Solomon for marrying the Queen of Sheba (now Ethiopia). Resins were the original antiseptic remedies, ground and applied as powders or pastes to wounds or inflamed tissues, and were also used for mummification. With alcohol distillation it was found that they could be dissolved in 90% alcohol and in this form they remain a most powerful mouthwash and gargle, for infected sore throats and gum disease. They never attracted much early research interest because they permanently coat expensive glassware! For use in the mouth, gums and throat hey are best combined with concentrated licorice extracts to keep the resins in suspension and add extra soothing properties. It appears that they work both as local antiseptics and by stimulating white blood cell activity under the mucosal surface. They feel extremely effective!
Salty
The salty flavour is immediately distinctive. A grain dropped onto the tongue is instantly moistening and a sprinkle on food enkindles digestion. This easily recognisable flavour has its receptors right at the front of the tongue. The salty flavor creates moisture and heat, a sinking and heavy effect which is very grounding for the nervous system and encourages stability. People who are solid and reliable become known as ‘the salt of the earth'.
Sharpness
The sharp taste of some fruits, and almost all unripe fruits, as well as vinegar and fermented foods, is produced by weak acids (the taste is generated by H+ ions from acids stimulating the sour taste buds). Sour taste buds are hard-wired to generate immediate reflex responses elsewhere in the body. Anyone who likes the refreshing taste of lemon or other citrus in the morning will know that one reflex effect is increased saliva production. Other effects are subjective rather than confirmed by research but there is a consistent view that they include increased digestive activity and contraction of the gallbladder.
Sweet
In the days when most people never tasted sugar, ‘sweetness’ was associated with the taste of basic foods: that of cooked vegetables, cereals and meat. In other words sweet was the quality of nourishment, and ‘tonic’ remedies. Describing a remedy as sweet generally led to that remedy being used in convalescence or recovery from illness. Interestingly, the plant constituents most often found in classic tonics like licorice, ginseng are plant steroids including saponins, which also have a sweet taste.

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