Q 3: Recreational drugs Flashcards
weed
Dried chopped bits of Cannabis sativa
66 IDed cannabinoids
Interact with CB1 receptors (in the brain) and CB2 receptors (peripheral)
Long history of use, modern varieties more potent than your dad’s
thc: the doped up feeling
thc today
used to be 1% now 20-30%
Clinical Effects of Marijuana in Dogs- #1 in dog
Lethal oral dose > 3 g/kg, but behaviorally effective dose 1000 times less
Effects in 30 – 60 min, peak in 2-3 hours
Usually depression, disorientation, vomiting, incoordination/ataxia, hyperesthesia, sleepy
Less often, apprehension, hyperexcitability, tremors, seizures, stupor, decreased heart rate and body temp, vocalization, snacky
Treatment: decontamination, monitor vitals (CV and respiratory function) , symptomatic/supportive care
Recovery 24 hours to 5 days (T1/2 25 – 30 hours)
half life of thc
25-30 hours- give activated charcoal
what is methylanthines
Alkaloids of plant origin, with similar toxic effects:
Caffeine – coffee and pills
Theophylline - tea
Theobromine - chocolate
caffeine and dogs
Coffee grounds in the rubbish bin
Caffeine supplements/pills (10 x 200 mg pills = LD50 dose for 40 lb dog)- will kill half the dogs
Caffeine powder (½ tsp = LD50 for 40 lb dog)
But …..not all chocolate is created equal
Made from cacao beans (seeds of Theobroma cacao). Theobromine concentration varies with the type of chocolate:
Milk chocolate = 50 mg/oz.
Dark/semi-sweet = 130 mg/oz.
Baking chocolate = 400 mg/oz.
White chocolate = < 1 mg/oz.
Clinical Effects of Chocolate Poisoning
Complex mechanism of action
Slowly absorbed and excreted, plasma T1/2 about 18 hours
1-4 hours, restless, hyperactive, panting, tremors, vomiting and diarrhea, increased heart rate, blood pressure and body temperature
Next few hours, cardiac arrhythmias, muscle rigidity and incoordination, CNS excitation
Seizures, coma, death in 18 hours to 3-4 days from cardiac or respiratory failure
Decontamination:
Make Thor vomit using 3% hydrogen peroxide
Give activated charcoal (repeat doses) to reduce uptake treatment
Decontamination:
Make Thor vomit using 3% hydrogen peroxide
Give activated charcoal (repeat doses) to reduce uptake from intestinal tract
IV fluids to enhance excretion in urine
Symptomatic and supportive care:
Control seizures and excitation
Monitor/manage heart rate and rhythm, and blood pressure
Prognosis is guarded due to dose – usually good if presented early
Nicotine Poisoning
From tobacco plants (Nicotiana) and their products
Cigarettes (10-30 mg each)
Cigars (100-450 mg each)
Chewing tobacco and snuff (13 – 17 mg/gram)
Nicotine patches (about 10-120 mg each)
Nicotine gum (2-4 mg/piece)
Mechanism of Action
Low doses mimic acetylcholine to stimulate post-synaptic nicotinic receptors in CNS, autonomic NS and at neuromuscular junctions of skeletal muscles
High doses cause persistent stimulation, leading to persistent depolarization of nerves and muscles, with exhaustion and failure (blockade)
Toxicity of Nicotine in Dogs
Toxic dose in dogs: oral LD50 = 9-12 mg/kg
Ingestion of 2 cigars or < 1 pack of cigarettes may be lethal to a 40 lb. dog, patches cause prolonged exposure
Rapidly absorbed across mucous membranes or skin
Rapid onset of initial GI effects – salivation, vomiting, diarrhea
Generally, CNS stimulation/excitation (tremors, agitation, incoordination, seizures), followed by CNS depression, depolarizing block of neuromuscular junctions leading to weakness and paralysis
Death from cardiac arrest or respiratory paralysis in 18-24 hours (or faster)
Treatment:
Decontamination/emesis or lavage, with activated charcoal, cathartic and diuresis (IV fluid administration to increase urinary excretion). Endoscopic removal of the patch.
Monitor/manage heart rate and blood pressure, seizure control, respiratory support
Prognosis poor for high doses not stabilized within 4 hours
