Nicotine Flashcards
What is nicotine?
Water soluble alkaloid from the dried leaves of tobacco plant (nicotiana tabacum)
How are animals exposed to nicotine?
Ingestion of contaminated feed or water
Ingestion of tobacco products
Readily absorbed through the MM and respiratory tract (GI tract absorption- acids delay, bases enhance)
Nicotine is highly toxic in what species?
Dogs
What are the exposure sources and their values?
Cigarette: 9-30 mg CIGAR: 45-150 mg (~5x a cigarette) Snuff: 12-16 mg Nicotine patches: 7-114 mg Gum: 2-4 mg per slice
What actions does nicotine have when entering the body?
Enters the body and is distributed rapidly through the bloodstream, including the CNS
What are the two principal oxidative metabolites?
Continine and nicotine oxide
Metabolites are inactive and excreted by the kidneys and excreted in the urine. Explain what happens to renal excretion in acidic and basic urine.
Renal excretion is DECREASED in ALKALINE or HIGH urine pH- therefore increased reabsorption
Renal excretion is INCREASED in ACIDIC or LOW urine pH
What is the MOA of nicotine?
Potent stimulant of parasympathetic nervous system
Cholinergic receptor agonist
Stimulates CRTZ to initiate vomiting
What are some of the clinical signs of nicotine toxicosis?
Early stimulation (ganglionic and neuromuscular) -ataxia, lethargy, hypersalivation, vomiting bradycardia, tremors
Later (or with high doses) nicotinic blockade
- CNS depression, tachycardia, vasodilation
- paralysis of respiratory muscles- RESPIRATORY FAILURE
How do you diagnose Nicotine toxicosis?
Hx of exposure, clinical signs, possibly lab testing
What is the treatment for nicotine toxicosis?
Decontamination Enhance excretion (diuretics) Atropine for parasympathetic effects Diazepam- seizures Mecamylamine- direct nicotinic antagonist prescribed for humans
What is the prognosis of nicotine toxicosis?
If animal survives first 4 hours, prognosis is good
- in dogs survival is grave to poor if large amounts ingested
