TOX 11 - Insecticides Flashcards
Chlorinated hydrocarbon insecticides
Acute rare, chronic more common
Inactivates Na+ in excitable membranes
Half life over 1 year, extremely slow elimination
Organophosphorus insecticides MOA, absorption and effect
irreversible cholinesterase inhibitors via phosphorylation of the esteratic site
Absorbed in skin, GI, resp. tract
Causes muscarinic excess
Organophosphorus insecticides treatment
oxime-agents
maintenance of vital organs
decontamination
atropine
Carbamate insecticides MOA
Reversible cholinesterase inhibitors
Absorption: skin, respiratory tract, GI tract
Shorter effect than organophosphorus type
Toxic effects: similar to organophosphate but with shorter duration (due to more rapid reactivation of the cholinesterase)
- Therapeutic index is larger with carbamates than organophosphates
Treatment is the same as organophosphorus insecticides
*decontamination, maintenance of vital signs, atropin
Nicotine
Well absorbed, incl. across skin
Toxic effects - CNS (resp. arrest, convulsions, coma) depolarizing SkM end plate blockade
Symptomatic treatment
Other natural insecticides
Rotenone
Pyrethrum
Pesticides are
chemicals that may be used to kill fungus, bacteria, insects, plant diseases, snails, slugs, or weeds among others.
These chemicals can work by ingestion or by touch and death may occur immediately or over a long period of time
Insecticides are
a type of pesticide that is used to specifically target and kill insects!
Organochlorine insecticides MOA, absorption, toxic effect, treatment
inhib. of Na+-ch. inactivation in excitatory membranes (→ rapid repetitive firing),
Ca2+ ion transport is inhibited (→ effect on repolarization and enhances the excitability of neurons)
- Absorption: skin, inhalation, oral ingestion
- Toxic effects: CNS stimulation (tremor, convulsions), possible carcinogenicity if chronic
- Treatment: no specific treatment for acute intoxication (only supportive/symptomatic), decontamination
Organochlorine insecticides- Absorption AND elimination?
- skin
- , inhalation,
- oral ingestion
extremely slow elimination (t½ = 1 year)
Organochlorine insecticides- Toxic effects
- CNS stimulation (tremor, convulsions),
- possible carcinogenicity if chronic
Treatment Organochlorine insecticides
no specific treatment for acute intoxication (only supportive/symptomatic),
decontamination
Organophosphorus insecticides absorption and effect
Absorption:
- skin,
- inhalation,
- oral ingestion -
Toxic effects: mimic the actions of parasymph. NS.
- Treatment: atropine, supportive treatment, decontamination
- Additional info: - Relatively unstable and break down in the environment due to hydrolysis and photolysis - Some agents are capable of phosphorylating a neural enzyme named neuropathy target esterase (NTE) → progressive demyelination → paralysis, axonal degeneration → organophosphorus ester-induced delayed polyneuropathy (OPIDP)
Treatment: organophosphorus insecticide
- atropine,
- supportive treatment,
- decontamination
organophosphorus insecticide additional info
- unstable and break down in the environment due to hydrolysis and photolysis -
- Some agents are capable of phosphorylating a neural enzyme named neuropathy target esterase (NTE) → progressive demyelination → paralysis, axonal degeneration → organophosphorus ester-induced delayed polyneuropathy (OPIDP)
