Botanical Name: Convallaria majalis, Liliaceae

Common names: Lily of the Valley, Convallaria.

Plant description: Convallaria arises from a creeping rhizome in early spring, sending up small shoots that emerge from a scaly sheath. As the dark green leaves lengthen and unfurl, a larger leaf can be seen to sheath a smaller one within it. The leaves are between 12-14 cm long and 2-4 cm wide, lanceolate, margin entire, with a prominent midrib, and parallel venation.  The leaves appear to grow with a slight slant backwards to catch the rain and feed it to the root stalk.  The flower stalk arises a short time later from the same sheath, beside the leaf stalk, bearing a number of greenish buds on the upper surface of the stalk.  When open the flowers are of the purest white, bell-shaped, and hang downwards, each bell with six scalloped-shaped edges that are folded back. By late summer the flowers have developed into scarlet berries.

Habitat, ecology and distribution: Convallaria is typically found growing wild the moist deciduous forests of Europe and Russia, and has naturalized in similar habitats in North America.  It is commonly found in gardens as a ground cover and border.

Part used: Rhizome.

Harvesting and collection: The rhizome is collected in late August.

History: The species name majalis refers to the goddess Maia, mother of Hermes, and in all the old herbals Convallaria was placed under his dominion. Although not commonly used in North America, Convallaria is an important remedy in Europe, and its use dates back at least as far as classical Greece, where the herbalist Apuleius describes that it was given to Asclepius by the god Apollo.  Grieve describes a legend in which it is the fragrance of Convallaria that "…draws the nightingale from hedge and bush, and leads him to choose his mate in the recesses of the glade (1971).

Constituents: Convallaria contains a variety of important glycosides, notably the cardioactive convallatoxin, which upon hydrolysis yields strophanthidin and rhamnose. Several other minor glycosides called cardenolides are also present however, such as cheirotoxin, convallarin, convallamarin, convallamarogenin, and convalloside, and although a few have also displayed cardioactive properties, there is none, including convallatoxin, that can account for the specific cardioactive properties of the whole herb.  A variety of saponin glycosides and flavonoid glycosides can also found in the herb, including quercitin and rutin, as well as a volatile oil.

Medical research:
•Cardiovascular: Weiss states that although convallatoxin has marked cardiac properties, the variety of other constituents found in the whole herb appear to modulate its effects.  Further, the absorption of convallatoxin is only about 10%, with a loss of action of 50% per day (Weiss 1988, 146). Convallatoxin was found to inhibit palytoxin (PTX) induced contraction and the loss of tissue potassium in rabbit and rat aortas. Other cardioactive glycosides such as convallatoxigenin, strophanthidin, digoxin and digitoxin failed to inhibit the PTX-responses.  The authors report that the results of the study suggest that the specific sugar moiety of cardiac glycosides is important for the inhibitory effect exerted (Ozaki et al 1984). Convallatoxin was found to interact with membrane phospholipids and promote the binding of calcium ions (Ivanov et al 1987). The effect of dietary cardiac glycosides upon blood pressure regulation was investigated in Sprague Dawley rats fed a synthetic diet.  The administration of convallatoxin in the drinking water was shown to delay the onset of the increase in blood pressure observed in the controls for 4 weeks. Plasma aldosterone levels were approximately doubled in the cardiac glycoside-treated groups. Higher plasma Na+ levels and hematocrit values present in the synthetic diet group were also normalized by the glycoside supplements. These results suggest that supplemental dietary cardiac glycosides exert bidirectional effects on blood pressure regulation through actions that modulate extracellular fluid and electrolyte balance (Tamura et al 2000).

Toxicity: Although Convallaria contains potentially toxic constituents, most experienced practitioners believe the whole herb to be remarkably well tolerated and unlike Digitalis, non-cumulative. Duke lists the LDLlo (lowest published lethal death) for the intravenous administration of convallatoxin in rats as 38 mg/kg (1985, 529).  The LD50 for the intraperitoneal administration for convallamarin is listed as 3400 mcg/kg (Duke 1988, 529).  At least one case of animal poisoning is reported in the literature (Moxley et al 1989).  The red berries are reported to be highly toxic (Weiss 1988, 145).

Herbal action: cardiotonic, diuretic, purgative, emetic

Indications: Heart irregularities due to organic tissue changes, mitral valve insufficiency, congestive heart failure, palpitation and arrhythmia, shortness of breath, diminished arterial pressure

Contraindications and cautions: functional cardiac disturbances, hypertension, pregnancy, lactation

Medicinal uses: The primary indication for Convallaria is cardiac debility, when there is evidence of obstruction and congestion. Palpitation, arrhythmia, feeble pulse, dyspnea, diminished renal excretion, hepatic torpor, venous stasis and generalized edema are typical symptoms of this form of cardiac insufficiency. Felter and Lloyd state however that Convallaria is not so much indicated in cases of organic degeneration as much as it is used for cardiac conditions of an obstructive nature, particularly where the mitral valves are involved (1893). In small doses Convallaria is considered a tonic to the heart, strengthening its action; in moderate doses it is indicated in cardiac excitation; and in while large doses Convallaria will increase heart action. Compared with digitalis, Felter and Lloyd state that Convallaria "…is generally as efficient, both as a heart tonic and as a diuretic, and in many cases is said to act better. It is safer than digitalis, which may destroy life by paralyzing the heart, an effect never produced by convallaria. Moreover, it is freer from cumulative effects. Vomiting, anorexia, disordered digestion, cerebral excitation, and pupillary dilatation, in addition to its acrid taste, make digitalis often an unpleasant remedy" (1893). 

According to Boericke the thoughts of the Convallaria are dull and the tongue is broad, with a thick heavy coating.  Typically, the patient feels better in open air and worse in a warm room (1927).

Pharmacy and dosage:
•Fresh Plant Tincture: 1:2, 95% alcohol, 5-20 gtt
•Dry Plant Tincture: 1:5, 65% alcohol, 5-20 gtt.
•Hot Infusion: 1:20, 30-60 mL

REFERENCES

Boericke, William. 1927. Hom¶opathic Materia Medica. 9th ed. Digitized version available from: http://homeoint.org/books/boericmm/c.htm
Duke, James. 1985. CRC Handbook of Medicinal Herbs. Boca Raton: CRC Press.
Evans, W.C. 1989. Trease and Evans Pharmacognosy London: BailliËre Tindall.
Felter, HW and JU Lloyd. 1893. King's American Dispensatory. Digitized version available from http://www.ibiblio.org/herbmed/eclectic/kings/main.html.
Grieve, Maude. 1971. A Modern Herbal. New York: Dover Publications.
Ivanov LV, Khadzhai IaI, Chueva IN, Makarevich IF.Farmakol. 1987. Effect of cardiac glycosides on the calcium ion binding by biomembrane lipids. Toksikol. Mar-Apr;50(2):30-2
Moxley RA, Schneider NR, Steinegger DH, Carlson MP. 1989. Apparent toxicosis associated with lily-of-the-valley (Convallaria majalis) ingestion in a dog. Am Vet Med Assoc Aug 15;195(4):485-7
Ozaki H, Nagase H, Urakawa N.J 1984. Involvement of the sugar moiety in the inhibitory action of the cardiac glycosides on the palytoxin-induced responses in vascular smooth muscles Pharmacol Exp Ther Oct;231(1):153-8
Tamura M, Utsunomiya H, Nakamura M, Landon EJ. 2000. Effect of dietary cardiac glycosides on blood pressure regulation in rats. Can J Physiol Pharmacol Jul;78(7):548-56
Weiss, Rudolf. 1988. Herbal Medicine. Translated by A.R. Meuss. Beaconsfield, England: Beaconsfield Publishers