Drugs-stimulants Flashcards
Toxidromes
Toxic syndromes- cluster of clinical signs characteristic of group of agents
Sympathomimetic toxidrome drugs
-caffeine
-cocaine
-amphetamines
-MDMA
-ecstasy
-high dose serotonergic drugs
-methylxanthines
-ephedrine
-bath salts
Sympathomimetic toxidrome clinical signs
Sympathomimetic toxidrome mechanism
Overstimulation of adrenergic, dopaminergic, and/or serotonergic receptors
-leads to vasoconstriction, increased cardiac contractility, CNS excitation
Antidepressants
-therapeutic use in vet med (behaviour modification, anxiety, aggression)
-Ex. clomipramine, amitriptyline, trazodone, fluoxetine, paroxetine, sertraline, selegiline
Antidepressant mechanism and target organs
Target: CNS and cardiovascular
Mechanism: overstimulation of serotonin, dopamine, and/or NE receptors
Onset of antidepressant med toxicity
As early as 30mins post exposure, but can be delayed up to 12-24hrs
Clinical signs of antidepressant med toxicity
Mild= lethargy, ataxia
Moderate to severe= serotonin syndrome
-GI (hypersalivation, vomiting, diarrhea)
-CNS (hyperexcitability, agitation, ataxia, mydriasis, tremors, seizures, hyperthermia)
-CV: tachycardia, hypertension, arrhythmias
*sometimes see ileus, urinary retention= anticholinergic toxidrome
Management of antidepressant med toxicity
-decontamination
-sedation (acepromazine)
-IVFT, methocarbamol, antiemetic therapy, seizure control, correlation of acid/base abnormalities, thermoregulation, low stimulation environment
-Antidote for serotonine syndrome= cyproheptadine
Diagnosis of antidepressant med toxicity
-history of exposure to owner medication
-clinical signs
-some LC/MS-MS screening
Prognosis for antidepressant medication toxicity
-excellent with prompt care
What drugs can lead to serotonin syndrome?
-antidepressant meds
-amphetamines (MDMA, ADHD Meds)
-5HTP
-tramadol
-fentanyl, cocaine, bath salts
-CYP inhibitors
Beta-2 receptor agonists
Blue inhalers (salbutamol)
-used in vet med for relief of bronchoconstriction in equine and feline asthma
Exposure scenarios of beta-2 receptor agonists
-chewed inhaler (hissing sound)
*dogs
-iatrogenic overdose possible
Beta-2 receptor agonists mechanism and target organ
Target: cardiovascular and CNS
Mechanism: causes overstimulation of beta receptors= loss of beta2 selectivity resulting in stimulation of beta 1 receptors
Onset of beta-2 receptor agonists
Peracute
Clinical signs of beta 2 receptor tox
-weakness, tachypnea, dyspnea
-vasodilation, hypotension
-loss of beta 2 selectivity= increased cardiac contractility, sinus tachycardia
-arrhythmias
-CNS: anxiety, restlessness, agitation, tachypnea, muscle tremors
Clinical pathology signs for beta-2 receptor agonist toxicity
-hypokalemia: weakness, PU/PD, decreased urine concentrating ability, ECG abnormalities
Beta-2 receptor agonist toxicity managment
-no decontamination
-antidote= beta blockers (propranolol)
-correct hypokalemia with potassium supplementation
-ECG, BP, IVFT, sedation, methocarbamol
Diagnosis of beta-2 receptor agonists
-chewed inhaler
-sympathomimetic toxidrome
Prognosis of beta-2 receptor agonists
Good with medical care
*guarded if severe tachycardia
Cocaine
-alkaloid from the coca plant
-therapeutic use in human medicine and common drug abuse
Mechanism and target organ of cocaine
Mechiansm: Blocks the reuptake of NE, 5HT, DA leading to increased catecholamine release= sympathomimetic
Target: CNS and cardiovascular
Amphetamines
-speed, ice, MDMA ecstasy/molly, others
-contained in ADHD meds, narcolepsy meds, weight loss meds
eg. Ritalin, Adderall
Amphetamine mechanisms
Increased release of 5HT, DA, NE
Onset of cocaine and amphetamine toxicity
Within 30mins of ingestion
Clinical signs of cocaine and amphetamine toxicity
Management of cocaine and amphetamine toxicity
-no antidote
-sedation, seizure control, thermoregulation, IVFT, beta blockers, ECG, blood gas
Diagnosis for cocaine and amphetamine toxicity
-history of exposure
-sympathomimetic toxidrome
-urine drug screen
Prognosis of cocaine and amphetamine toxicity
depends on severity of clinical signs and response to supportive care
Sympathomimetics
