Snowy Aconite (Xueshang Yizhihao/Radix Aconiti Brachypodi)
Snowy Aconite (Radix Aconiti Brachypodi) is a perennial herbaceous plant in the Ranunculaceae family, genus Aconitum. The root is upright, carrot-shaped with a brown outer skin. The stem is upright, either unbranched or branched, covered with sparse, curved, and appressed short hairs. The leaves are alternate, broadly ovate, and either hairless on both sides or with sparse short hairs on the veins of the underside. The inflorescence is terminal and dense, with leaf-like bracts; the fruit is a follicle; and the seeds are numerous. The flowering period is from September to October, and the fruiting period is from October to November. Snowy Aconite is named for its appearance resembling mugwort and its growth in alpine meadows.
Snowy Aconite is distributed in the southwestern part of Sichuan and the northwestern part of Yunnan. It commonly grows in alpine meadows at high altitudes, often on shady slopes, with soil best being fertile, loose, black humus soil. It is usually propagated by seeds and root buds.
Snowy Aconite has some medicinal value; it is bitter, pungent, and warm in nature, entering the liver and kidney meridians. It can be used to dispel wind and dampness, disperse blood stasis and reduce swelling, invigorate blood circulation, relieve pain, and detoxify carbuncles. However, due to its highly toxic nature and lack of proper preparation, it is not suitable for internal use.
Botanical History
Snowy Aconite is named for its growth in alpine meadows and its mugwort-like appearance.
Morphological Features
Snowy Aconite is a perennial herbaceous plant in the Ranunculaceae family, genus Aconitum. The tuberous root is obconic, 2.3-3.6 cm long, 9-11 mm in diameter, or nearly cylindrical, about 7 cm long and 5 mm in diameter. The root is upright with a carrot-like brown outer skin. The stem is upright, 40-65 cm tall, either unbranched or branched, covered with sparse, curved, appressed short hairs, and leaves are spaced evenly along the stem. The lower leaves wither during flowering. The middle stem leaves have short petioles and are hairless; they are alternate, leathery, pentagonal, sometimes roundish or broadly ovate, 5.5-9 cm long, 8-10 cm wide, with a base that is heart-shaped or shallowly heart-shaped, sometimes round, deeply three-lobed to 1.5-2 cm from the base, with central lobes that are ovate-diamond-shaped, gradually tapering, with edges sparsely toothed with triangular teeth, and veins somewhat raised forming an obvious network. The leaves are hairless on both sides or with sparse short hairs on the veins of the underside; the petioles are 2.2-3 cm long and cylindrical. The upper stem leaves become smaller, broadly ovate or diamond-shaped, three-lobed slightly beyond the middle, sometimes narrowly ovate, with few divisions. The inflorescence is terminal and dense, with 1-6 flowers, 2.2-3 cm long; the peduncle and pedicels are hairless; the pedicel is about 1 cm long and slightly bent downward. The bracts are leaf-like, with small bracts that are lanceolate to lance-shaped linear, 3-8 mm long and about 1.5 mm wide, almost hairless; the calyx is blue, with the upper calyx lobe helmet-shaped or high helmet-shaped, 2.4-3.2 cm high, 5-10 (-15) mm wide, hairless, with the lower edge slightly concave, 1.5-2.4 cm long; the petals have long claws, hairless, with large lobes, the lip about 6 mm long, the spur 5-7 mm long, curved backward; the stamens are hairless, with filaments having 2 small teeth or entire; the pistil has 3 carpels, hairless. The achene is 1.6-1.8 cm long; the fruit is a follicle; the seeds are numerous, obconic-triangular, about 2 mm long, with transverse membranous wings on the surface. Flowering occurs from September to October, and fruiting from October to November.
Habitat and Distribution
Snowy Aconite (Radix Aconiti Brachypodi) is found in the southwestern region of Sichuan and the northwestern region of Yunnan. It typically grows in alpine meadows at altitudes of 3000-4000 meters, favoring shady slopes with fertile, loose black humus soil.
Cultivation Techniques
Snowy Aconite is generally propagated by seeds or root buds.
Seed Propagation: Seeds are sown in early May, spread evenly, and the soil should be kept moist. After one year of seedling growth, the plants can be transplanted.
Root Bud Propagation: The upper third of the root is cut off and, before or just after the first snowfall in November, the root buds are planted at a spacing of 21 cm x 21 cm, 4-6 cm deep.
Field Management: Regular weeding is necessary. To promote healthy growth, apply soil manure or wood ash once a year.
Main Value
Snowy Aconite has notable medicinal properties; it is bitter, pungent, and warm in nature, and enters the liver and kidney meridians. It is used to dispel wind and dampness, reduce blood stasis and swelling, invigorate blood circulation, relieve pain, and detoxify carbuncles. However, due to its highly toxic nature and lack of proper preparation, it should not be taken internally.
Pharmacological Properties:
- Taste and Nature: Bitter, pungent, warm, with significant toxicity. It enters the liver meridian.
- Functions: Dispels wind-dampness, invigorates blood circulation, and relieves pain.
- Applications: Useful for various types of pain, as it is warming and dispersing, and effective in treating many kinds of pain. It is also used for carbuncles, tumors, insect and snake bites, with external application recommended for such conditions.
Botanical Pharmacology
Modern clinical research indicates that Snowy Aconite is warm, bitter, and pungent, with significant toxicity. It can dispel wind and dampness, reduce inflammation, and relieve pain. It is used for rheumatic bone pain, bruises, and toothaches with notable efficacy. Due to its toxicity, it is primarily used externally, and internal use should be under strict medical supervision. Typical internal dosage ranges from 25-50 mg per day, with a maximum of 70 mg.
Snowy Aconite’s pharmacological components, including aconitine, benzoylaconine, and others, have analgesic effects, with some showing strong local anesthetic properties. For instance:
- Aconitine and benzoylaconine exhibit significant pain relief.
- 3-acetylaconitine is a non-addictive painkiller with effects on inflammation and tissue swelling.
- Aconitine also has a digitalis-like effect on frog hearts, counteracted by atropine.
Toxicity and Safety
Snowy Aconite is extremely toxic, and its treatment dose is close to its toxic dose. It has been included in the National Special Management Drug list due to its severe toxicity. In mice, the median lethal dose (LD50) for aconitine is about 0.08-0.3 g/kg body weight, with signs of toxicity including strong vagal nerve stimulation, salivation, vomiting, abdominal pain, arrhythmias, hypotension, shock, respiratory distress, or convulsions leading to coma or death.
Precautions:
- Toxicity: Highly toxic; internal use requires proper preparation and strict dosage control.
- Contraindications: Avoid use in pregnant women, the elderly, children, and patients with heart disease or ulcers.
- Dietary Restrictions: Avoid raw, cold foods, legumes, and red meat during treatment.
- Alcohol: Avoid alcohol-based preparations internally.
In case of poisoning, symptoms include severe vagal nerve stimulation and may lead to respiratory and circulatory failure.
Chemical Components
Snowy Aconite (Radix Aconiti Brachypodi) contains various alkaloids, including:
- Aconitine
- Deoxyaconitine (3-deoxyaconitine)
- Acetylaconitine (3-acetylaconitine)
- Penduline (snowy aconitine)
- Laxiconitine
- Songorine (from Xuanwei Aconite)
- Neoline
- 14-Acetylneoline
- Denudatine
- Songoramine
- Flavaconitine
- Virescenine
- Aconifine (also known as nagarine)
Usage and Dosage
Dosage:
- Oral Administration: Common dose is 25-50 mg. Maximum dose is 70 mg.
- External Use: Apply an appropriate amount mixed with alcohol.
Clinical Applications:
- Pain Relief:
- Effective for various types of pain including rheumatic pain, neuralgia, toothache, trauma pain, postoperative pain, and cancer pain. Can be used in powdered form, mixed with alcohol for external application, or as an injection.
- Treatment of Sores and Toxicities:
- Used for sores, swelling, and insect or snake bites. The toxic properties can be harnessed to counteract other toxins when applied externally.
Usage Precautions:
- Internal Use: Must be processed and dosed carefully. Not suitable for pregnant women, the elderly, children, or individuals with heart conditions or ulcers.
- Dietary Restrictions: Avoid raw, cold foods, legumes, and red meat during treatment. Avoid alcohol-based preparations internally.
Modern Research
Chemical Constituents:
- Includes several types of aconitine, such as aconitine, deoxyaconitine, acetylaconitine, penduline, and others.
Pharmacological Effects:
- Pain Relief: Various alkaloids in Snowy Aconite exhibit significant analgesic effects. For example, 3-acetylaconitine is a non-addictive painkiller with effects on inflammation and tissue swelling. The total alkaloids of the plant have strong local anesthetic properties.
- Cardiac Effects: Shows digitalis-like effects on frog hearts; these effects can be counteracted by atropine.
- Anti-Cancer: Xuanwei Aconite has demonstrated anti-tumor properties.
- Reproductive Effects: Some alkaloids have been noted for anti-fertility activity.
- Toxicity: Can cause arrhythmias and hypotension.
Clinical Research
Clinical Applications:
- Used as an injectable or topical treatment for rheumatic arthritis, joint pain, trauma, fractures, and postoperative pain with notable efficacy.
- A study used a formulation of Snowy Aconite powder with wintergreen leaf powder and other ingredients to treat patellar fractures, showing significant effectiveness in 42 out of 50 cases.
Adverse Reactions:
- Toxicity: Overdose, ingestion of raw or improperly processed form, or misuse with alcohol can lead to severe poisoning, including abdominal pain, vomiting, salivation, numbness, palpitations, hypotension, dizziness, muscle rigidity, seizures, and potentially death.
- Treatment for Poisoning: Early gastric lavage, intravenous fluids, and atropine administration are recommended. Additional treatments include quinidine, procainamide, and supportive therapies with substances like bamboo shoots, coriander, and licorice.
Additional Information
Other Variants Used in Folk Medicine:
- Liangshan Aconite (Aconitum liangshanicum)
- Jiangzi Aconite (Aconitum ludlowii)
- Short-stalked Aconite (Aconitum sessiliflorum)
Snowy Aconite is a potent medicinal herb with a range of applications but requires careful handling due to its high toxicity.
