PPT Toxicology Q1

opioids, clonidine, phenothiazines, and cholinesterase inhibitors

constriction of the pupil (miosis)

antidote of heparin

protamine sulfate

poison control center enhancement and awareness act of 2000

provided federal funding for poison control centers. - established a nationwide toll- free number to access a poison control center

when a specific antidote or other treatment is under consideration

quantitative laboratory testing may be indicated

salicylates, carbon monoxide, and other toxins that produce metabolic acidosis or cellular asphyxia

rapid respirations

poison prevention packaging act of 1970

required child resistant caps on medications

federal anti-tampering act of 1983

required tamper evident packaging on OTC products

food, drug, and cosmetic act of 1938

required testing for drug safety

atropine and other anticholinergic agents, and cocaine and other sympathomimetic drugs

twitching and muscular hyperactivity

what is the toll free number

1-800-222-1222

antidote of acetaminophen

acetylcysteine (acetadote, mucomyst)

antidote of iron salts

deferoxamine

alcohol, hydrocarbon solvents, or ammonia

odor in the mouth

corrosive substances, or soot form smoke inhalation

signs or burns

Poison Prevention Week

third full week in march

Calcium channel blockers

- calcium antagonist can cause serious toxicity or death with relatively small overdoses. - depress sinus node automaticity and slow AV node conduction, reduce cardiac output and blood pressure. - overdose of verapamil and diltiazem are generally more dangerous, resulting in bradycardia, hypotension, and cariogenic shock. - dihydropyridines are more selective for vascular calcium channels resulting in vasodilation, hypotension, and reflex tachycardia. - in massive overdose, this selectivity may be lost, and all the listed cardiovascular effects can occur with any

tricyclic antidepressants (amitriptyline, desipramine, doxepin)

- can cause life threatening drug overdose. - Ingestion of more than 1g of a tricyclic (or 15-20mg/kg) is considered potentially lethal - are competitive antagonist at muscarinic cholinergic receptors, and anticholinergic findings - some are strong a blockers, which can lead to vasodilation - triicyclics inhibits the cardiac sodium channel, causing slowed conduction with a wide QRS interval and depressed cardiac contractility.

GI tract

- for most ingestions, clinical toxicologists recommend simple administration of activated charcoal to bind to ingested poisons in the gut before they can be absorbed - in unusual circumstances, gastric lavage or whole bowel irrigation may also be used. Inducing emesis is ineffective and potentially harmful and is no loner recommended

Newer antidepressants (fluoxetine, paroxetine, citalopram, venlafaxine)

- generally safer then the tricyclic antidepressants and monoamine oxidase inhibitors, although they can cauase seizures. - SSRIs may interact with each other or especially with monoamine oxidase inhibitors to cause the serotonin syndrome, characterized by agitation, muscle hyperactivity, and hyperthermia. - Bupropion (not an SSRI) has caused seizures even in therapeutic doses. Some antidepressants have been associated with QT prolongation and torsades de pointes arrhythmia

antipsychotics

- include older phenothiazines and butrophenones, as well as newer so-called "atypical" drugs. - Can cause CNS depression, seizures, hypotension, and QT prolongation - The potent dopamine D2 blockers are also associated with parkinsonian movement disorders and in rare cases with the neuroleptic malignant syndrome, characterized by "leap-pipe" rigidity, hyperthermia, and autonomic instability

Beta blockers

- inhibit both B1 and B2 adrenoceptors, selectivity is lost at high doses.

hemodialysis

- more efficient - assists in correction of fluids and electrolyte imbalance, acid-base status, and may also enhance removal of toxic metabolites

American association of poison control centers

- national nonprofit organization representing each of the 55 poison control centers , the more than 1,700 professionals these centers employ, as well as other poison- related organizations. AAPCC's mission is to actively advance the health care role and public health mission of its members through information, advocacy, education, and research

Monoamine oxidase inhibitors (tranylcypromine, phenelzine)

- older antidepressants that are occasionally used for resistant depression. Can cause severe hypertensive reactions when interacting foods or drugs taken, and they can interact with the selective serotonin reuptake inhibitors

Cholinesterase inhibitors

- organophosphate and carbamate cholinesterase inhibitors are widely used to kill insects and other pests. - most serious cases= result from intentional ingestion by suicidal person, but poisoning has also occurred at work or rarely, because of food contamination or terrorist attack

Aspirin (salicylate)

- salicylate poisoning is much less common cause of childhood poisoning deaths since the introduction of child-resistant containers and the reduced use of children's aspirin. It still accounts for numerous suicidal and accidental poisoning. - Acute ingestion of more than 200 mg/kg is likely to produce intoxication. - poisoning can also result from chronic overmedication, the occurs in elderly patients using for chronic pain - poisoning causes uncoupling of oxidative phosphorylation and disruption of normal cellular metabolism.

decontamination

- should be undertaken simultaneously with initia stabilization, diagnostic assessment, and laboratory evaluation - involves removing toxins from the skin or gastrointestinal tract

iron and other metals

- widely used OTC - as few as 10-12 prenatal multivitamins with iron may cause serious illness in a small child. - poisoning with other metals (lead, mercury, arsenic) are also important, especially in industry

What dose of naloxone should be given

0.4-2 mg IV

How much dextrose should children be given?

0.5g/kg (2mL/kg of 25% dextrose)

Alcoholic or malnourished patients should receive what to prevent Wernicke syndrome?

100 mg of thiamine IM or IV

Where was teh first poison control center established

1953 in Chicago

How much dextrose should adults be given?

25g (50mL of 50% dextrose solution) IV

poison prevention

America's 55 poison centers receive millions of calls, the majority of which are about people coming into contact with dangerous or potentially dangerous substances. The rest were calls for information

What type of patients may appear to be intoxicated, and there is no rapid and reliable way to distinguish them from poisoned patients

Hypoglycemic

antidote of warfarin

Vit. K (phytonadione)

anticholinergic agents

a large number of prescriptions and nonprescription drugs, along with various plants and mushrooms can inhibit the effects of acetylcholine at muscarinic receptors. Some drugs used for other purposes have anticholinergic effects, in addition to other potentially toxic actions.

Toxin

a poisonous substance of natural origin - plant, animal, bacterial, fungal (society of toxicology)

cathartics

administration of a cathartic (laxative) agent may be hasten removal of toxins from the GI tract and reduce absorption, although no controlled studies have been done.

charcoal does bind to

alcohols and cyanide

antidote of snake or spider bites

antivenin

Poison

any substance, either taken internally or applied externally, that is injurious to health or dangerous to life - stedmans medical dictionary

antidote of anticholinesterase agents, organophosphates

atropine, pralidoxime

activated charcoal

can adsorb many drugs and poisons. most effect if given in the ratio 10:1

antihistamine such as diphenydramine

can cause seizures

Xenobiotic

compounds exogenous (external) to normal metabolism of the organism - foreign compounds (society of toxicology)

skin

contaminated cloting should be completely removed and double bagged to prevent illness in health care providers and for possible laboratory analysis

antidote of cyanide

cyanide antidote kit (amyl nitrite, sodium nitrate, sodium thiosulfate), hydroxocobalamin

antidote of digoxin

digoxin immune Fab (digibind, DigiFab)

amphetamines, cocaine, LSD, and atropine,a nd anticholinergic drugs

dilation of pupils (mydriasis)

antidote of heavy metals

dimercaprol, penicillamine, calcium EDTA, succimer (specific antidote use varies by metal)

dextrose

every patient with altered mental status should receive a challenge with concentrated dextrose, unless a rapid bedside blood glucose test demonstrates that the patient is not hypoglycemic.

organophosphates, nicotine, and sympathomimetic drugs

excessive sweating

larger doses of naloxone may needed for patients with overdose involving

fentanyl, codeine, and other opioids

sedative-hypnotic or other CNS depressant intoxication and may be mistaken for brain dealth

flaccid coma with absent reflexes and even an isoelectric electroencaphalogram may be seen with deep coma

benzodiazepine antagonist

flumazenil

antidote of benzodiazepines

flumazenil (romazicon)

antidote of ethylene glycol, methanol

fomepizole

serotonin syndrome

generalized hypertonicity of muscules and lower extremity clonus

phenytoin, alcohol, barbiturates, and other sedative drugs

horizontal nystagmus

organophosphates, iron, arsenic, theophylline

hyperactive bowel sounds, abdominal cramping, and diarrhea

amphetamines, cocaine, and antimuscarinic drugs

hypertension and tachycardia

sympathomimetics, anticholinergic, salicytes, and drugs producing seizures or muscular rigidity

hyperthermia

calcium channel blockers, B blockers, clonidine, and sedative-hypnotics

hypotension and bradycardia

tricyclic antidepressants, trazodone, quetiapine, vasodilators, and B agonist

hypotension and tachycardia

CNS-depressant drug especially when accompanied by exposure to a cold environment

hypothermia

gastric lavage

if patient is awake or if the airway is protected by an endotracheal tube this may be used by using orogastric or nasogastric tube-- as large as tube as possible

antimuscarinic, opioid, and sedative drugs

ileus

cannabidiol

important component of cannabis, appears to be devoid of most of the mood-altering effects of THC

charcol does not bind to

iron, lithium, or potassium

peritoneal dialysis

it is a relatively simple and available technique, it is inefficient in the removing of most drugs

amphetamines and other stimulants

methamphetamine (crank, crystal), methyenedioxymethamphetamine (MDMA, ecstasy), cocaine (crack) along with pseudophedrine and ephedrine. Caffeine is often added to dietary supplements sold as "metabolic enhancers" or "fat burners".

haloperidol, and other antipsychotic agents, and by strychnine or by tetanus

muscular rigidity

antidote of opioids

naloxone

opioid antagonsit

naloxone

phenytoin, carbamazepine, alcohol, and other sedative intoxication

nystagmus, dysarthria, and ataxia

acetaminophen

one of the drugs commonly involved in suicide attempts and accidental poisonings, both as the sole agent and in combination with other drugs - acute ingestion o fmore than 150-200mg/kg (children) or 7g total adults. - a high toxic metabolite is produced int the liver

hemodialysis is especially useful in

overdose cases in which the precipitating drug can be removed, and fluid and electrolyte imbalances are present and can be corrected

medical or clinical toxicology

pathophysiology, diagnosis, and treatment of clinical problems related to poisoning and drug intoxication

forced diuresis

previously popular but of unapproved value, may cause volume overload and electrolyte abnormalities

pure food and drug act of 1906

prohibited adulteration and misbranding of foods and drugs

What is the most toxic B blocker?

propranolol - could be because propranolol in high doses causes sodium channel-blocking effects similar to those seen with tricyclic antidepressants, and it is lipophilic, allowing it to enter the CNS

federal caustic poison act of 1927

requirements for poison warning labels

federal hazardous substances labeling act of 1960

requirements for warning labels on hazardous household chemicals

antidepressants ( especially tricyclic antidepressants and bupropion), cocaine, amphetamines, theophylline, isoniazid, and diphenhydramine.

seizures

tricyclic antidepressants can cause

severe cardiovascular toxicity

circulation

should be asses by continuous monitoring of pulse rate, blood pressure, urinary output, and elevation of peripheral perfusion. An intravenous line should be placed, and blood drawn for serum glucose and other routine determinations

breathing

should be assessed by observation, pulse oximetry, end tidal carbon dioxide monitoring, and, if in doubt, by measuring arterial blood gases. Patients with respiratory insufficiency should be intubated and mechanically ventilated.

airway

should be cleared of vomitus, or any other obstruction and an oral airway or endotracheal tube inserted if needed

when should flumazenil not be used

should not be used if there is a history of tricyclic antidepressant overdose or a seizure disorder

atropine and other antimuscarinics

skin appears flushed, hot, and dry

the inital management of a patient with coma, seizures, or otherwise altered mental status should follow the same approach regardless of the poison involved

supportive measures are the basics (ABCDs) of poisoning treatment

what should be brought to the emergency department

syringes, empty bottles, household products, OTC meds in the immediate vicinity of the possible poisoned patient

marijuana

tetrahydrocannabinol (THC) - responsible for most of its mood-altering effects - exposure to THC is increasing due to legalization for both medical and recreational use. - synthetic cannabinoids marked as "herbal incense" or "spice" may cause marked stimulate effects, psychosis, and seizures

occupational toxicology

the field of toxicology that examines chemicals found in the work place including identification of agents with potential toxicity and conditions under which those agents can be used safely

forensic toxicology

the measurement of alcohol, drugs and other toxic substances in biological specimens and interpretation of such results in medicolegal context

Toxicokinetics

the study of the absorption, distribution, metabolism, and excretion of a xenobiotic under circumstances that produce toxicity

Toxicology

the study of the adverse effects of chemical, physical or biological agents on living organisms and the ecosystem - includes the study of mechanisms of action, toxicokinetics, and toxicodynamic of toxins and prevention, diagnosis, and treatment of toxic exposures

environmental toxicology

the study of the potentially deleterious impact of chemicals presents as pollutants of the environment on living organisms

Toxicodymanic

the study of the relationship od toxic concentrations of xenobiotics to clinical effect