Chapter 33: Irritant Poisons

Cobra venoms

Cobra venoms

________ are quite toxic and they are a major cause of human envenoming morbidity and mortality.

Instantaneous death

________ due to shock due to fear of snakebite is observed more often than the actual toxicity of the venom.

Antivenom

________ is expensive, always in short supply, and has a limited shelf life.

Neurotoxic factor

________ can mimic strychnine poisoning.

Hemolytic factors

________ can mimic viperine snakebite.

Bullae

________ can be aspirated to dryness with a fine sterile needle.

Calcium gluconate

________ given intravenously can reduce edema /rash.

Atropine

________ may be given to reduce the pulmonary edema (do not use morphine)

Snakes

________ like cobra can inject /emit venom by spitting.

Vomitus

________ shows normal contents initially, but later turns bilious or contains altered blood.

Adrenocorticotrophic hormone

________ (ACTH) 25 mg in 1000 ml normal saline given as an intravenous drip can help in prevention of severe allergic reactions.

Scorpion

________ is a poisonous insect (Arthropod) with a crab like body with eight legs and a segmented tail having a bulbous expansion and a sting in the last segment which has a clear, colourless venom (toxalbumin) having two components, a hemolytic and a neurotoxic fractions.

Centipedes

________ belong to Myriapoda (under class Arthropods) and are organic animal irritants.

absolute contraindication

There is no ________ to antivenom in patients with life- threatening systemic envenomation.

rapid immobilization

Venom may have several functions for the snake such as ________ and predigestion of prey.

Tongue

________ is forked at the tip and serves as a sense organ and can be protruded out even when the mouth is closed through a gap in the upper jaw.

Snake venoms

________ are usually clear and amber-colored fluid when fresh.

Snakes

________ are ectothermic (cold- blooded) limbless vertebrates of the Class Reptilia.

Antivenom

________ is not always necessary; many patients are bitten by nonvenomous snakes, and a large portion of those bitten by venomous snakes are not envenomated.

Antivenoms

________ have a range of specific and paraspecific neutralizing activity and are useless for venoms outside that range.

Irritant poison

mainly produce inflammation on the site of contact, especially in the gastrointestinal tract, respiratory tract, and skin

Jacobsons organ

a cavity in the roof of the mouth with olfactory cells in which the snake inserts the tips of the forked tongue

Colubridae

They rely instead on the trauma caused by other teeth to provide an entry track for their “venom”

Elapidae

They have small to moderate-sized fangs at the front of the mouth, possibly the “true fangs”.

Viperidae

All species have well-developed, longer fangs on hinged maxillae, allowing rotation (elevation) when biting, than in any other groups of venomous snakes.

Hydrophiidae

These are sea snakes and are closely related to the cobras, with similar fang structure, but live most or all of their lives in an aquatic, usually marine environment.

Atractaspidae

These are side fanged viper like snakes confined to Africa and the Middle East. They have unusual fang structure and venoms, which contain endothelin-like compounds called sarafotoxins, causing potent smooth muscle contraction.

Neurotoxic Venom

Venom common is Elapidae Snakes.

Hemotoxic Venom

Venom common in Viperidae snakes

Myotoxic Venom

Venom common in hydrophidae or sea snakes.

Phosphorus

It acts as a protoplasmic poison due to which normal metabolism is disturbed and cellular oxidation is severely affected

Chlorine

It acts as a direct irritant of the mucous membrane of the respiratory tract by locally forming hydrochloric acid as it comes in contact with moisture.

Bromine

• It is a reddish-brown liquid, volatilizing to red fumes at room temperature and emitting an unpleasant odor.

• It is more often n use as medicine and act as a sedative and cough elixir.

Iodine

• A volatile crystalline substance with purple glittering color, a characteristic odor, and an acrid taste. It gives violet fumes/vapors at room temperature.

• It acts as an antiseptic. It is a powerful irritant and vesicant.

Formaldehyde

• A colorless gas with a pungent odor. Commercially it is available as formalin, which is a 40 percent aqueous solution of formaldehyde gas.

• A disinfectant, antiseptic, deodorant, tissue fixative, and embalming agent.

Arsenic

It is not poisonous as it is insoluble in water and cannot be absorbed from the gastrointestinal tract.

Metallic Mercury

______ is a heavy, silvery liquid and is nonpoisonous. But it volatilises at room temperature and inhalation of vapors is toxic.

Lead

_____ compounds can act by producing spasms of the capillaries and arterioles or by fixation of the poison in the tissues such as brain, bones, etc.

Copper sulfate

_______ is a crystalline salt with blue color and has a metallic taste. In small dose of 0.5 gm it acts as an emetic, but in large doses it acts as an irritant poison. Poisoning is usually accidental or suicidal.

Iron

Its early features of poisoning are due to the corrosive effects of iron, while later effects are largely due to the disruption of the cellular prAbrus Precatoriusocesses.

Abrus Precatorius

It is a slender vine and climber, with compound leaves having 10-15 pairs of narrow leaves, small pinkish flowers with seedpods which split open when ripe exposing 4-6 seeds within.

Ricinus Communis

It is a large shrub with greenish-red leaves. Fruits are borne in clusters and are soft-spined greenish/ brownish capsules with seeds.

Croton Tiglium

It is an evergreen tree with smooth ash-colored bark. The leaves of the tree are ovate-lanceolate. Flowers are small, and oblong. Fruits are three lobed containing oval, dark brown seeds, with brownish black colour and longitudinal striations.

Calotropis

It is a tall shrub with yellowish-white bark, and oblong thick leaves and purplish or white flowers.

Semicarpus Anacardium

It is a small tree of East Indian origin. Its flower is dull/greenish yellow in colour. Fruit is black, heart- shaped with hard rind within which is a thick fleshy pericarp which yields brown oily resinous fluid.

Capsicum Annum

It is a small herb bearing somewhat long, tapering fruits, which become red when ripe, and possess a pungent odor and taste.

Eucalyptus Globus

It is a tall tree with smooth bark, long curved leaves, and large flowers. Eucalyptus oil obtained by steam distillation of the extract derived from the leaves.

Azadirachta Indica

It is a tree. Seed grown in the tree yields a yellowish oil (margosa oil), which has a disagreeable odour and bitter taste.

Colchicum Autumnale

Perennial herb (Category: Bulbs) Height: 15-30 cm, with basal, slender leaves; and long, tubular, 6-parted, flowers which are pink, violet/ lavender or white in colour.

Ergot

It is the sclerotium (mycelium) of a fungus Claviceps purpura, which grows on many cereals like rye, barley, wheat, oat, etc. fungus gradually replaces the whole grain to a dark purple mass, which on drying yields ergot.