35.1: Oleanders

• Oleanders are widely cultivated in gardens in India for their ornamental flowers.

• Acts like Digitalis, which can produce malignant dysrhythmias and cardiac failure, cardiac arrest and convulsions with lethal dose.

Plant Varieties and Descriptions

1. Nerium odourum

   • A plant with white/pink fragrant flowers, which are 2-5 cm in width and have five petals, or in double blooms with many petals.

   • The leaves are narrow, lanceolate, leathery, dark green on the upper surface, lighter beneath, and 10-25 cm long.

   • Fruits turn brown, dries, and split, releasing small seeds tipped with brown hairs.

   • Toxic Principles: Neriodorin, Neriodorein, Karabin, Oleandrin, Folinerin, & Rosagenin.

   • Fatal Dose: 15 gm of root.

   • Fatal Period: 24-36 hrs.

   • Symptoms: Nausea, vomiting and pain abdomen, restlessness, slow and weak pulse. Soon, respiration becomes hurried. Victim may suffer dysphagia; lock jaw, etc. followed by tetanic convulsions, leading to exhaustion, drowsiness, coma, heart failure and death.

2. Cerbera thevetia

   • A plant with yellow, bell-shaped flowers which are 5-7 cm long and 5 cm wide, the five lobes are spirally twisted and spreading.

   • Leaves are lanceolate.

   • The fruit is globular, light green, about 4 to 5 cm in diameter and contains a single nut, which is triangular with deep groove along the edge.

   • Each nut contains five pale yellow seeds.

   • The seeds contain five percent of cardiac glycoside.

   • Toxic Principles: Thevetin, Thevitoxin, Nerifolin, Peruvoside, Ruvoside, & Cerberin.

   • Fatal Dose: 10 seeds.

   • Fatal Period: If powdered and fed to a child mixed with milk – 3 hours.

   • Symptoms: Burning sensation in mouth, tingling of tongue, dryness of throat, vomiting, diarrhea, headache, dilated pupils, irregular action of heart followed by drowsiness, coma, collapse and death.

3. Cerbera odollum

   • A small plant or a shrub.

   • Leaves are dark green, fleshy and lanceolate, 20– 30 cm long and 4–6 cm broad.

   • The flowers are white, like those of jasmines.

   • The fruit resembles an unripe mango, is globular and dark green and has a thick fibrous mesocarp, which encloses a single seed usually.

   • The seed is flattened and ovoid and contains two kernels which are partly white, and when dry it may have bluish tinge or become gelatinous.

   • Milky acrid juice exudes from all parts of the plant.

   • Toxic Principle: Cerberin

   • Fatal Dose: Kernel of one fruit.

   • Fatal Period: 1-2 days.

   • Symptoms: Same as for cebera thevetia.

Signs and Symptoms

• Oleander poisoning in general closely resembles digitoxin poisoning with predominantly gastrointestinal and cardiac symptoms.

• All gastrointestinal symptoms manifest within several hours. Serious toxic effects result from cardiotoxicity and specifically from ventricular ectopy and cardiovascular collapse.

• Conduction delay may persist for 3 to 6 days, displaying classical digitalis toxicity as characterized by increased ectopy and conduction delay.

Treatment

• Treatment is mainly supportive.

• Gastric lavage, fluid administration, atropine, isoproterenol, antiarrhythmics, and early administration of activated charcoal may be beneficial.

• Hemodynamic decompensation may require temporary use of cardiac pacemaker and digoxin-specific Fab antidote fragments. Doses of 200 mg and 480 mg intravenously have improved life-threatening oleander intoxication.

35.2: Aconite

• Aconite is a large herb, with palmate leaves and white or blue showy flowers.

• The whole plant is poisonous.

• Roots s are highly toxic and are used commonly.

  • They have a conical, tapering shape with a wrinkled appearance (5-10 cm long) and a bittersweet taste. Apparently, it resembles the edible horse radish.

• Toxic principles are diterpene alkaloid, known as aconitine, misaconitine, and hypaconitine are.

• Diterpene alkaloids are known neurotoxins that can cause conduction block and paralysis through their action on voltage-sensitive sodium channels in the axons.

  • This can result in initial neurological stimulation, followed by depression of myocardium, smooth and skeletal muscles, central nervous system (CNS) and peripheral nervous system.

• Aconite is absorbed via skin and oral route.

• Fatal Dose:

  • 1 gm of root (Indian)

  • 250 mg of root extract

  • 20 drops of tincture extract

  • 3 to 5 mg (average 4 mg) of alkaloid – Aconitine.

• Fatal Period:

  • 3 to 24 hours maximum (average 6 hours).

Signs and Symptoms

• Symptoms generally appear within 30 to 90 minutes after ingestion of the poison and lasts up to approximately 30 hours.

• Palpitation, hypertension, ventricular ectopics/ arrhythmias

• Nausea, salivation, pain in stomach, vomiting, and diarrhea

• Paresthesia, tingling and numbness in the lips, mouth, tongue, and pharynx.

  • It may extends all over the body, followed by profuse sweating, weakness impending paralysis of the extremities and/ seizers. Deep tendon reflexes may be absent.

• There may be difficulty in vision due to hippus, which means initially there is alternate dilatation and constriction of pupils, followed by complete dilation.

• The conscious state of the victim may also be reduced.

• Hypertensive, sustained, ventricular tachyarrhythmias are the direct cause of death. Convulsions and respiratory paralysis may also precede death.

• Manifestations of acidosis and hypokalemia are also often seen.

Treatment

• Gastric lavage with warm water, and weak solution of iodine in potassium iodide or tannic acid to precipitate the alkaloid, or animal charcoal.

• Artificial respiration (oxygen)

• Atropine – 1 mg, given to prevent vagal inhibition of heart.

• 0.1% Novocain – 50 ml controlling the cardiac arrhythmias.

35.3: Nicotine

• Nicotine grows in all tropical regions of the world.

• Nicotine contains an alkaloid known as nicotine, which is a colorless liquid that turns amber on exposure to light.

• Stimulation and depression followed by paralysis of cells of the peripheral autonomic ganglia, midbrain, spinal cord, muscles, etc.

• Nicotine is absorbed via intact skin and oral mucosa, GI tract and respiratory system. It is detoxified in the body, mainly in the liver, but also in the kidneys and lungs. The major metabolic product of nicotine is cotinine, which with a non-metabolized form of nicotine is excreted in urine.

• Elimination is complete in 16 hours. An acidic urine increase urinary excretion. Nicotine is also excreted in the milk of lactating woman.

• Fatal Dose:

  • 2 gm of tobacco or 60 mg of nicotine.

  • One cigarette usually contains 1 gm of tobacco and 15-25 mg of nicotine.

  • Usually a nonfiltered brand cigarette smoke contains 1.2 to 2.4 mg and filtered brands between 0.2 to 1.0 mg of nicotine per cigarette and 5 ml of the nicotine insecticides.

• Fatal Period:

  • A few minutes to a few hours.

Signs and Symptoms

• Mild Poisoning

  • Frequently occurs by chewing the dried leaves producing dizziness, nausea, vomiting, headache, perspiration, weakness, cardiac irregularities, etc. Victim will turn normal in a few hours.

• Acute Poisoning

  • Occurs schiefly due to the central/ peripheral stimulations.

  • Manifestations include all mild poisoning features mentioned above and other findings such as burning in mouth, throat, stomach, prostration, etc. followed by convulsions and cardiac irregularities, sometimes even cardiac arrest and death.

• Nicotine Withdrawal Symptoms

  • Considerable evidence that nicotine is a highly addictive substance exists.

  • Nicotine withdrawal symptoms can be prolonged and debilitating.

• Chronic Poisoning

  • Victims may manifest with chronic cough, bronchitis, laryngitis, pharyngitis, dermatitis, angiospasms, tremors, amblyopia and narrowing of field of vision, blurring, etc.

  • The effect of nicotine on the heart is called “tobacco heart”, characterized by extra-systole, angina, etc.

  • Chronic cases may also frequently manifest with thromboangiitis obliterans (TAO) of extremities.

Treatment

• Gastric lavage with activated animal charcoal

• Purgative

• Atropine 1.5 mg (if there is salivation)

• Cardiorespiratory stimulants

• Symptomatic treatment

• Stop smoking permanently in TAO cases.