Another traditional use for rue is as an anthelmintic. Dioscorides wants it boiled in olive oil and drunk to remove intestinal worms. This indication passes down through the Arabic and Renaissance sources, then is rarely mentioned, although Cullen recommends a strong decoction as an enema for ascarides in the rectum. Williamson states that the herb is reportedly anthelmintic and recent ethnobotanic research shows that rue is a popular traditional medicine in rural parts of Italy for worms and externally against head lice and parasites. Despite being a non-indigenous herb, it is also in much demand by the people of the Bredasdorp/Elim area of South Africa not only for worms but also for bladder and kidney problems, convulsions, diabetes, fever, headache, stomach complaints and sinus problems, in doses of 1 teaspoon of the herb to a cup of boiling water. An anthelmintic action is derived from the volatile oils and bitterness of rue and leads us to consider the plant’s actions in the digestive tract. Dioscorides notes that eaten or drunk it stops diarrhoea and, taken with dried dill Anethum graveolens, abdominal colic. Pliny says that the pounded leaves in wine with cheese are given to patients with dysentery. Rue soon relieves indigestion, flatulence and chronic stomach pains, and should be decocted with hyssop Hyssopus officinalis and taken in wine for colic and internal haemorrhage, and can be used externally on the abdomen and over the heart, as discussed above. Decocted with figs in wine, and the liquid reduced by half then drunk, it treats dropsy. Pliny wants rue for liver problems generally and the Arabic writers mention the spleen. Indications for diarrhoea, flatulence and colic have passed down the tradition to the present day. Hoffmann emphasizes the spasmolytic action of rue, easing griping and bowel tension by relaxing smooth muscle. When Fernie (1897) suggests that rue remedies the nervous indigestion and flatulence from which the Greeks suffered when eating before strangers and later mentions that it sometimes causes vomiting or purging, we wonder if he is a victim of the confusion between wild rue and harmal. Grieve too, following the National Botanic Pharmacopoeia, warns of taking rue after food ‘on account of its emetic tendencies’, whereas Bauhin proposes half a drachm (2 g) of the powdered herb in warm wine to comfort the stomachs of children weakened by frequent vomiting.
Rue has also been recommended for lung problems and its spasmolytic action offers a rational therapeutic for respiratory complaints. Only pleurisy is included in the unverified uses of the Commission E monograph, which disease fits the report of Dioscorides that the herb is ‘good for pains on the side and chest, dyspnoea, cough, inflammation of the lungs’. Pliny mentions asthma but the British Herbal Pharmacopoeia restricts itself to an antitussive action without indications and the National Botanic Pharmacopoeia lists only croupy affections. Hoffmann suggests spasmodic coughs. Indeed little has been made of rue for lung problems since Culpeper’s day, when rue may also have been given for purulent expectoration and the spitting of blood, using for the latter three sprigs of rue boiled in wine. Rather, the spasmolytic action combined with a stimulating effect has been thought useful for nervous complaints. The old herbals mention more serious neurological problems: Pliny proposes a decoction of the juice for epilepsy and Fernie (1897) writes that the Neapolitan physician Piperno commended rue in 1625 as a specific for epilepsy and vertigo. We may recall the Commission E noting dizziness as an adverse effect; Fernie mentions an unsteadiness of gait in regard to excessive doses, for a leaf or two chewed is sufficient in his opinion to relieve nervous headache, giddiness, hysterical spasm or palpitation (the praecordial pain in Apuleius for which the herb in wine is drunk before the patient lies down), and Grieve and Hoffmann repeat this advice. Quincy reckons that rue is good in all convulsive cases and thinks the best way to take it is to eat the fresh leaves with bread and butter. Cullen too is prepared to consider rue, ‘a plant of several peculiarities’ in the treatment of epilepsy, for which the inspissated juice or other extract may be used. Ibn Sina advocates rue internally and externally for paralysis and sciatica, for which latter Fernie suggests that the leaves should be bruised and applied. Macer recommends the bruised herb with cumin powder applied to an ache in any part. Indeed, an external liniment of rue is used topically for pain in present-day Mexico. For lethargy, Turner’s ‘the forgetful disease’, rue may be taken internally, as an enema or the vinegar of the fresh plant smelled. In Apuleius rue in vinegar is poured onto the head and in the Old English Herbarium it is sprinkled onto the temples. For instance, some recent research records application of a homoeopathic combination of rue and calcium phosphate in the treatment of neurocysticercosis which has neurological symptoms as the cysts are in the brain tissues. Thirty-six patients were assessed with computerized tomography scans and treated for between 3 and 65 months, and 25 subjects became symptom-free.
The indication of paralysis is not continued, although Gerard writes of oil of rue warming and chafing all cold members that are rubbed with it. Instead Quincy naturally places rue among the hysterics, with cephalic qualities, and good for all nervous complaints in women which originate from the womb. Miller, Hill, Cullen, the National Botanic Pharmacopoeia and the British Pharmaceutical Codex (1934) follow suit. In the last case a dose of 0.12-0.3 mL of the oil should be taken on sugar or in hot water. The essential oil of rue is no longer recommended and indeed Wren prefers anyway an infusion of 1 oz to 1 pint (25 g to 500 mL), to be taken in cupful doses for hysteria and amenorrhoea. He warns that large doses are liable to produce inflammation and nerve derangements.
The Commission E monograph lists several adverse effects of rue on the nervous system: melancholic moods, sleep disorders, tiredness, dizziness and spasms. lust as we have seen with dizziness above, these anecdotal reports are likely to be linked with excessive dosage. It is not news to practising herbalists that a certain action of a herb obtained with a therapeutic dose can be paradoxically reversed with a different dose, usually a much larger one but also with micro-doses. Melancholy, poor sleep, tiredness and spasms may appear in the same disease, and may be provoked by inappropriately large doses of a stimulant medicine such as rue. On the other hand, there are two reports in the literature we have consulted about the generation of melancholy. Turner cites Simeon Seth (although this same statement does not appear in Fuch’s citation) on the need for those of a choleric temperament suffering from an imbalance of the yellow bile humour to abstain from rue, since it will heat their blood too much, driving off the thinner part of it and leaving it melancholic in quality. Fernie (1897), not being attached to Galenic theory, mentions dullness and weight of mind as products of excessive dosage of rue. It is important with this herb, as we have heard several times, to establish a correct dosage for the indication.
A final set of indications listed by Dioscorides for internal use of rue is pains of the hip joints and of the joints, and internal swellings and oedema. These passed down through the Arabic and Renaissance writers before being neglected. Treatment of the joints may be carried out by internal medicine and by external applications, as we have seen. A piece of recent research hints at some credence to the advice in the old herbals. An extract of rue was found to have an antiinflammatory action in vitro in a model which measures nitric oxide production and showed that this was related to inhibition of nitric oxide synthase. The authors found that although it was much more effective than pure rutin, the action was also related to concentration of rutin. Williamson mentions the antioedema effect of rutin and cites other research on the antiinflammatory action of rue. There are other plants which are safer sources of rutin, as we have already stated, but the unusual constituents of rue – aliphatic ketones, furocoumarins and alkaloids – may have specific actions of their own to complement this antiinflammatory effect.
We have seen a range of dosages employed in the above uses of rue, from the dew shaken from the flowers for an eye bath and a couple of fresh leaved chewed for nervous headache, palpitation and giddiness, to 2 oz of the fresh herb infused in a pint of beer for snake bite. This last use is unlikely to be repeated by herbal practitioners in a primary care setting, so we should instead consider the typical doses advocated. Again these have been as small as 2 tablespoons twice daily of an infusion made with a small teaspoon of rue to a glass of water, and as large as Weiss’ infusion to obtain the benefits of rutin from rue, where 1-2 tablespoons of dried herb per cup of boiling water is used and the infusion taken three times daily. The British Herbal Pharmacopoeia states 0.5-1 g of the dried herb, as infusion, or 0.5-1 mL of the liquid extract 1:1 25% alcohol, three times daily. Grieve proposes 15-30 grains (1-2 g) of the powdered herb and 0.5-1 drachm (1.7-3.5 mL) of the liquid extract. Hoffmann offers a tincture dosage of 1-4 mL of tincture 1:5 40% alcohol. Wren states 1 oz of dried herb infused in 1 pint of boiling water, the infusion taken in cupful doses.
Bauhin writes that he must limit his comments on rue to what he himself has experienced of its efficacy, since it is virtually impossible to investigate the many claims made for rue by other authors. He provides instructions on how to prepare a distilled water, a conserve, a vinegar and an oil. For the latter, chopped and crushed fresh rue is infused in oil for 15 days in the sun or in a warm place, then decocted in a bain marie. The oil is strained and the process repeated twice more. As far as dosage is concerned, he proposes 1 drachm (4 g) of the powdered herb in warm wine for headaches due to cold. A handful of the (fresh?) herb decocted in wine until reduced by one third then strained, and with 4 oz sugar added, forms a drink for chest pain due to cold, to be taken morning and evening. In addition, 4 oz of the juice mixed with 1 drachm (4 g) of asafoetida seed Ferula assafoetida taken in a warm drink is helpful for epilepsy.