Is Aconitum (Ranunculaceae) Poisonous, Why It Easily Causes Poisoning, and How It Differs from Lindera and Fuzi

Aconitum, a plant of the Ranunculaceae family, its mother root is called Aconitum (Wutou), used as an anticonvulsant, to treat wind-induced paralysis and rheumatic neuralgia. So, is Aconitum poisonous? How does it easily cause poisoning? How does it differ from Lindera (Wuyao) and Fuzi?

1. Is Aconitum poisonous?

Aconitum is poisonous; it is an essential herb for dispelling cold and relieving pain, able both to dispel cold from the meridians and to disperse cold from the zang-fu organs. However, it is highly toxic and should be used with caution.

2. How does it easily cause poisoning?

1. Decoction time too short

Prolonged decoction of Aconitum or the recently adopted high-pressure steaming method can reduce its toxicity. If the condition requires an increased dosage of Aconitum, prolonged decoction is even more advisable. Too short a decoction time easily leads to poisoning. Aconitum must never be used raw.

2. Not processed (paozhi)

Aconitum is highly toxic, so it must be processed before internal use, and prescriptions for internal use should also specify processed Aconitum or processed Chuanwu, processed Caowu. Taking it unprocessed can cause poisoning even in very small amounts.

3. Cumulative poisoning

Long-term use of Aconitum can accumulate in the body and cause poisoning, especially in patients with liver and kidney insufficiency, who are more prone to this type of poisoning. If the condition requires long-term use of preparations containing Aconitum, an intermittent dosing method can be used. After taking it for several days or weeks, pause for 1 week. In addition, daily dosing can adopt a method of small amounts taken multiple times, dividing the total daily amount into several doses, which helps with the excretion of toxins.

4. Excessive dosage

Aconitum is divided into Chuanwu and Caowu. Caowu is more toxic. Because of differences in harvest time, processing, and decoction time, the toxic dose of Aconitum varies greatly. For Chuanwu it is 3-30 grams, for Caowu 3-4.5 grams, and oral aconitine at 0.2 mg can cause poisoning. Chuanwu poisoning can present with numbness of the mouth and tongue and the whole body, nausea and vomiting, chest tightness, spasms, difficulty breathing, decreased blood pressure, failure of body temperature to rise, arrhythmia, unclear consciousness, coma, and even death from circulatory and respiratory failure. The symptoms of Caowu poisoning are basically the same as those of Chuanwu. The toxic dose of Aconitum-type herbs varies greatly among individuals; some develop poisoning after decocting and taking only 6 grams of Chuanwu, and some after taking only 1 gram of Caowu. Therefore, special attention should be paid to the early symptoms of poisoning and treatment should be given as early as possible. In clinical use, Aconitum should also be started with small doses for trial.

5. Improper combination

Earlier practitioners believed that Aconitum should not be used together with Fritillaria (Beimu), Bletilla (Baiji), Pinellia (Banxia), or Trichosanthes (Gualou). In addition, there are clinical reports of poisoning caused by using Aconitum together with Ephedra (Mahuang).

3. How does it differ from Lindera (Wuyao) and Fuzi?

★Lindera (Wuyao)

Lindera (Wuyao), pungent in taste and warm in nature, is the tuberous root of a shrub in the Lauraceae family. The ancients believed the best place of origin for Wuyao was Tiantai Mountain in Zhejiang, and there is a formula called Tiantai Wuyao San, which was meant to convey that Wuyao produced at Tiantai Mountain was of very good quality. However, modern clinical research has found that there is no great difference in the quality of Wuyao produced in various regions, and moreover, Tiantai Mountain is now a nature reserve, so there is basically no more Tiantai Wuyao, and thus the name Tiantai Wuyao no longer exists.

Lindera (Wuyao) mainly has two major effects: one is to move qi and relieve pain, and the other is to warm the kidney and dispel cold.

Moving qi and relieving pain mainly acts on the spleen and stomach, and can also be used for the liver. Lindera (Wuyao) has a great advantage in moving qi and relieving pain, namely that its qi-moving and pain-relieving action is broad; this herb is warm in nature, and Bencao Qiuzhen says “for all diseases belonging to qi counterflow with chest and abdominal discomfort, this is suitable…… this is where counterflow evil runs across the chest, reaching everywhere, so it is used as an essential herb for counterflow evil in the chest and abdomen”; therefore, for the chest, hypochondrium, and epigastrium and abdomen, with appropriate combination, it can be used.

Warming the kidney and dispelling cold is its special effect, mainly used to treat frequent urination or enuresis caused by deficiency cold of the kidney and bladder and insufficient qi transformation, as in Suoquan Wan, which is Wuyao combined with Yizhiren and Chinese yam. For other patterns of kidney yang deficiency, Wuyao is generally not used.

★Fuzi

Pungent and sweet in taste, greatly hot in nature, and toxic; it is the daughter root of the Ranunculaceae plant Aconitum, and is a different part of the same plant as Chuanwu: Chuanwu is the mother root, and Fuzi is the daughter root, with toxicity slightly weaker than Chuanwu.

The first major effect of Fuzi is to restore yang and rescue from counterflow, which is the maximal application of its yang-warming effect, mainly used for severe yang collapse patterns with cold limbs, profuse sweating, and a faint pulse on the verge of extinction; combined with ginseng, which greatly tonifies original qi, it forms Shenfu Tang, specifically for the dual collapse of qi and yang.

For general yang deficiency patterns and patterns of yang deficiency and decline of the heart, spleen, and kidney, Fuzi can of course also be used, but for these patterns, using Fuzi is somewhat overkill.

In addition, the yang-warming effect of Fuzi can also be used for the limbs and meridians, that is, its effect of warming the meridians and unblocking the collaterals; for wind-cold-dampness bi patterns with obvious pain in the bones and joints of the whole body, it has a relatively strong cold-dispelling and pain-relieving effect, slightly weaker than Chuanwu.

The caution for using Fuzi is also that it should be decocted for a long time, preferably for 60 minutes, until there is no numb-spicy sensation when tasted. It is contraindicated in yin deficiency with yang hyperactivity and in pregnant women. In addition, Fuzi also belongs to the Aconitum-type drugs, so the drugs of the eighteen incompatibilities are also prohibited.