(Family ranunculaceae)

Aconitum napellus.

Aconitum napellus

Botanical origin Aconitum napellus. Plant family Ranunculaceae. Urdu name Zahreela poda. English name Aconite. Chemical class Alkaloids. Part used Roots.

Pharmacognostic features

Chemical constituents : Aconitine,hypaconitine,mesaconitine, jesaconitine.

Pharmacological actions : Antipyretic ,local anaesthetic,anti inflammatory,sedative,diuretic,antineuralgic,antirheumatic,atrabilious-antiphlegmatic disorders (leprosy,leucoderma,asthma,chronic ulcer).

Constituents and uses

Availability/dosage form : As tincture,tea,liniment,oinment. Must be used in detoxified form.

Dose: 60 mg of the root per dose. Pure aconite 2mg or aconite plant 1g may cause

death.

Availability and dose

Anabolic effects.Mesaconitine;accelerate liver synthesis by increase of RNA polymerase. Analgesic effects.Mesaconitine;release of nor-adrenaline(neurotransmitter) by nor-adrenergic pathway that block pain sensation. Anti inflammatory effects.Methanol extracts of aconitum;block histamine that is inflammatory mediator. Anti pyretic effect.Mesaconitine-hypothermic effects. Cardiovascular effects.Aconitine;mediated by alpha-adrenergic pathway. Endocrine effects.Aconitine;reduce plasma glucose level. Immunological effects.Aconitine;stimulates the response of IFN-gamma-activated expression of an antigen by macrophages by increasing plasma corticosterone level. Neuromuscular blockade effects.Aconitine;block sodium channels in nerve membrane.

Mechanism of action of drug

Anti-arrhythmic medications may antagonize the effects of aconite and increase the risk of cardiotoxicity or other side effects.

It lowers blood sugar levels. Caution is advised when using medications that may also lower blood sugar.

It may lower blood pressure. Caution is advised when using medications that may also lower blood pressure.

Combined use of aconitine with anesthetic medications or diuretic medications (those that increase urine flow) may also lower blood pressure.

Digoxin may interfere with aconitine effects on the heart.

Drug interactions of aconite

The cardiotoxicity and neurotoxicity of aconitine and related alkaloids are due to their actions on the voltage-sensitive sodium channels of the cell membranes of excitable tissues, including the myocardium, nerves, and muscles.

Aconitine and mesaconitine bind with high affinity to the open state of the voltage-sensitive sodium channels at site 2, thereby causing a persistent activation of the sodium channels, which become refractory to excitation.

The electrophysiological mechanism of arrhythmia induction is triggered activity due to delayed after-depolarization and early after-depolarization.

The arrhythmogenic properties of aconitine are in part due to its cholinolytic (anticholinergic) effects mediated by the vagus nerve.

Aconitine has a positive inotropic effect by prolonging sodium influx during the action potential. It has hypotensive and bradycardic actions due to activation of the ventromedial nucleus of the hypothalamus.

Toxicity/over dose

The neurological features can be sensory (paresthesia and numbness of face, perioral area, and the fore limbs), motor (muscle weakness in the fore limbs), or both.

The cardiovascular features include hypotension, chest pain, palpitations, bradycardia, sinus tachycardia, ventricular ectopics, ventricular tachycardia, and ventricular fibrillation.

The gastrointestinal features include nausea, vomiting, abdominal pain, and diarrhea.

Clinical features/symptoms

Avoid use of larger dose then recommended. Soaking and boiling or decoction preparation will hydrolyze

alkaloids into less toxic and non toxic derivatives. Management of aconite poisoning is supportive, including

immediate attention to the vital functions and close monitoring of blood pressure and cardiac rhythm.

Inotropic therapy is required if hypotension persists and atropine should be used to treat bradycardia.

Available clinical evidence suggests that amiodarone and flecainide are reasonable first-line treatment. In refractory cases of ventricular arrhythmias and cardiogenic shock, it is most important to maintain systemic blood flow, blood pressure, and tissue oxygenation by the early use of cardiopulmonary bypass.

Management

Contraindications : Don’t take orally or apply to skin during pregnancy and

breast feeding. It is contraindicated in patients with coronary

disease,cardiac disfunction,arrhythmias .Side effects : Cause tingling and numbness when applied topically. Cause hypotension,hypokalemia,leukocytosishypothermia,hyperventilation,clonic convulsions. Cause ventricular tachycardia,muscle

cramps,diarrhea,respiratory dipression,ataxia, blurred vision,liver and kidney damage, nausea, vomiting, dizziness.

Contraindications and side effects

http://www.ncbi.nlm.nih.gov/pubmed/19514874 (toxicity,clinical features,management).

http://herbsdatabase.blogspot.com/2012/07/aconitum-chasmanthum.html (uses and pharmacognostic features).

http://www.sigmaaldrich.com/life-science/nutrition-research/learning-center/plant-profiler/aconitum-napellus.html (chemical constituent and mechanism of action).

http://www.livingnaturally.com/ns/DisplayMonograph.asp?StoreID=E32FA6C399AB4C99897032581851D45D&DocID=bottomline-aconite (interaction with drugs and side effect and contraindications).

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