Now that we have returned to medicinal virtues of vervain, let us look at the medieval sources. The Old English Herbarium lists one internal use of the powdered herb peristerion, taken in drink to disperse poison, and 11 indications for vermenaca. These include liver pain, headache, wounds of various kinds including the bites of snakes, spiders and mad dogs, ‘for those who have clogged veins so that blood cannot get to the genitals’, an indication recalling the employment of vervain in love magic, and for those who cannot keep their food down. Two new uses are mentioned: for bladder stones and for swollen glands. Grieve tells us that the name vervain comes from the Celtic ‘fer’ and ‘faen’ meaning ‘to drive away the stone’. The Salernitan herbal specifies the root in mead for bladder stones, Macer wants equal parts of vervain, betony Stachys officinalis and saxifrage in white wine and Fuchs cites Aetius of Amida and Simeon Seth on the herb taken in drink with honey for unspecified stones. Parkinson and Culpeper after him state that vervain cleanses the kidneys and bladder of humours which engender stones, and helps to break stones and expel gravel. Quincy comments more generally on indurations and obstructions of the liver, spleen, kidneys and mesentery, Coffin lists diuretic and anti-scorbutic actions and both Priest & Priest and Bartram refer to vervain’s influence on hepatic and renal function. Stainton (1990) makes it a kidney tonic and Chevallier suggests a use in gall-stones. It is reasonable to identify a herbal diuretic action and there is also some evidence that vervain can be useful in cases of urinary stones.
As for swollen glands, this is named scrofula by the Myddfai physicians and vervain as a simple is recommended to be inwardly taken and externally applied, using the whole plant, until the swelling is dispersed. Hildegard describes topical compresses for swellings of the throat and corroding ulcers. The juice of vervain boiled in wine with honey is proposed by the teachers of Salerno for any swelling, growth or abscess of the throat which hinders swallowing. This may include scabs of the tonsils and takes us back to Dioscorides, but the recommendation for scrofula is not passed down into Renaissance herbals. There is a surprise re-appearance, however, in Victorian England, when Fernie (1897) writes that ‘the vervain has fallen of late years into disfavour as a British Herbal Simple, though a pamphlet has recently appeared, written by a Mr Morley, who strongly advises the revived use of the herb for benefiting scrofulous diseases. Therein it is ordered that the root of vervain shall be tied with a yard of white satin ribband round the neck of the patient until he recovers. Also an infusion and ointment are to be prepared from the leaves of the plant’. A prescription for scrofula is also recorded by lohn Skelton in The Science and Practice of Medicine, published by the National Association of Medical Herbalists of Great Britain in 1904 but with an introduction by the author from 1870. A decoction of vervain, coltsfoot Tussilago farfara and the poisonous dog’s mercury Mercurialis perennis and spurge laurel Daphne laureola, with added poke root Phytolacca americana and Spanish juice (liquorice Glycyrrhiza glabra) is prescribed for internal administration, while the enlarged glands are covered with flannel during the day and treated with hot wormwood compress at night. A poultice of white pond lily Nymphaea alba is used instead if the glands appear ripe for suppuration. The detail of Skelton’s treatment suggests actual use but for reasons of likely toxicity could no longer be repeated today.
Another medieval topical use for vervain involves applying the fresh juice to the chest while the herb is available, or the dried and powdered herb with honey in winter, for chest complaints. The Myddfai physicians recommend this to counter the effects of scrofula on the lungs, while the Salernitan herbal insists the plants used must be gathered when the sun is at its highest point, presumably mid-summer rather than noon. Macer accounts the herb generally good for stomach, liver and lungs and Fuchs reads the same in his copy of Pliny, the interpolation emphasizing the benefits of vervain for consumption.
The Byzantine sources Aetius of Amida and Simeon Seth cited by Fuchs, and Paul of Aegina cited by Dalechamps, provide yet more external uses: hair loss, toothache and loose teeth, mouth ulcers and fistulae. To these are added abdominal colic, elephantiasis, epilepsy, common or quotidian fevers, gout and hip pains by internal medicine. These citations appear where we might have expected comments in Renaissance herbals on new uses of vervain among contemporary doctors. The plant’s common name ‘simpler’s joy’ might suggest an enthusiastic usage outside trained medical practice, especially given the extent of vervain’s reputation in magic, and the popular tendency to deploy elaborate rituals in the use of medicinal plants. Could a superstitious reverence of the plant have diminished its standing among more qualified and professionally aware practitioners? Some writers want to distance themselves from such practices. Gerard chooses Dioscorides’ recommendation of vervain in agues to reprimand improper practice:
It is reported to be of singular force against the tertian and cjuartaine fevers: but you must observe mother Bumbies rules to take just so many knots or sprigs and no more, least it fall out so that it do you no good, if you catch no harme by it. Many odde olde wives fables are written of vervaine tending to witchcraft and sorcerie, which you may reade else where, for I am not willing to trouble your eares with reporting such trifles, as honest eares abhorre to heare … Most of the later physitions do give the juice or decoction hereof to them that have the plague: but these men are deceived, not only in that they looke for some truth from the father of falsehood and leasings, but also because in stead of a good and sure remedy they minister no remedy at all: for it is reported that the Divell did reveale it as a secret and divine medicine.
Quincy cites a magical use of vervain from Marcellus Empiricus, a Gallic physician of the 5th century AD and author of a book on medicines (De Medicamentis), before complaining that ‘many country people pretend to do great feats with it in agues, by applying it to the wrist in the form of a cataplasm, and also to cure gouty pains and swellings being use in the same manner’. Miller and Hill describe only physical applications: Miller recommends vervain for diseases of cold and phlegm, for clearing obstructions of the liver and spleen including jaundice, for gout and watery, inflamed eyes already mentioned by Parkinson, and as a vulnerary; Hill comments only on its ability to warm the stomach, open the liver and spleen and, with continued use, to remove nervous conditions. This last indication may stem from Parkinson’s opinion that the herb is good for those who are frantic and is the earliest mention we have found of vervain’s primary indication today.
Parkinson also establishes other indications, which will have been read more often in Culpeper’s rendering of the same virtues of vervain. He emphasizes benefits for defects of the stomach, liver, spleen, kidneys and also the lungs, treating cough, wheezing and breathlessness, and generally for all inward pains. It will cause a good color in the face and body. Vervain kills worms in the belly and its distilled water, dropped into the eyes for films and mists ‘wonderfully comforteth the optick veins’. Among the external uses are ointments for pain and swelling in the groin and for haemorrhoids, the juice or bruised herb to cleanse pustules, freckles and morphew (possibly a type of psoriasis). He lists gout and fistulas, which we have already seen mentioned in Byzantine sources.