Presentation on theme: "Plant Poisoning Dr. Ravi Nanayakkara. Objectives Introduction, classification and identification of poisonous plants. Circumstances, route of entry, metabolism."— Presentation transcript:
Objectives Introduction, classification and identification of poisonous plants. Circumstances, route of entry, metabolism and excretion of plant poisons. Mechanism of action, target organs, clinical features(early and late phase) and principles of management. Autopsy features(external and internal) and sample collection.
Plant poisoning More than 300 poisonous plants. Some are edible. Act on more than one organ, but act principally on one organ system.
Toxic substances Atropine Hyoscine Hyocyamine Scopolamine All are alkaloids
Circumstances Accidental –Children eat the seed or fruit Eating the leaves (mistakenly) Intentional – for revenge, confuse an enemy to robbery – mix with thalaguli during long distance bus travels Suicidal ingestion rare.
OrgansPathophysiologyClinical Features CNSStimulation Followed by depressionEuphoria, delirium aggression, terrifying hallucinations, bizarre behaviour, confusion, convulsions, increased muscle tone, Unconsciousness HeartParasympathetic block — > stimulationTachycardia, hypertension, Tachyarrythmias rarely SkinInhibition of sweat glands, Dilatation of blood vessels Dry, hot Flushes Eyes Relaxation of radial muscles of pupils, Inhibition of lachrymal glands Mydriasis and blurring of vision, photophobia, Dry eyes Alimentary tract Inhibition of salivary glands,Inhibition of intestinal musculature leading to relaxation Dry mouth, Reduced gut motility GUT Relaxation of detrusor muscleUrinary retention
Principles of Management Eliminate the poison Phytostigmine to reverse the action Diazepam to control fits Manage complications accordingly
Strychnos Nux vomika Goda/Divi kaduru Spinal stimulant Commonly found in Southern costal area. Toxin is mainly found in seeds. Poison – Strychnine ( an alkaloid)
Circumstances Accidental – Children eat fruit Suicidal rare due to bitter Homicidal rare due to bitter Abstract of seeds(strychnine) is used to as a rodenticide, kill stray dogs by injecting with a long stick Homicidal injection - rare
Absorption All mucosal surfaces Rapidly absorbed via GIT and spread throughout body
Patho – physiologySymptoms and signsTime of onset after ingestion Acute inflammation of alimentary tract mucosa due to local actions of salicylic acid and benzoic acid burning pain, numbness, itching and tingling around mouth and throat. Nausea, vomiting, dehydration, thirst, blood and mucus diarrhoea within 6- 12 hrs Augmentation by choline of autonomic contraction of smooth muscles throughout the body. In gastrointestinal tract, bronchi, uterus abdominal colic, ileus, tenesmus, breathlessness abortion within 6- 12 hrs Block of mitosis, by cholchicine in bone marrow→ bone marrow aplasia→ Throinbocytopenia bleeding gums, easy bruising within 6 hrs Acute tubular necrosis of the kidney decreased urine output, haematuria Central nervous system stimulation, then depression. Respiratory centre depression Restlessness, confusion, delirium, convulsions, coma Breathlessness after 36 hrs Arrest of cell division in hair follicles Rapid shedding of stratum corneum Alopecia, generalized depilation Dermatitis after 1-2 weeks
Principles of management Gastric lavage Activated charcoal Management of complications
Autopsy Features of acute dehydration and GI irriration Features of complication
Ricinus communis(Endaru) Entire plant is poisonous Seeds most poisonous Grows throughout the island