Toxicology Flashcards
Toxicology
The study of toxic or poisonous substances.
Poision
Substance whose chemical action could damage structures or impair function when introduced into the body.
Drug
Substance that has some therapeutic effect when given in the appropriate circumstances and appropriate dose.
Toxins
A poison or harmful substance produced by bacteria, animals or plants.
Bioavailability
The percentage of unchanged substances that is present in the systemic circulation
Half-life
Amount of time needed for the average person to metabolize or eliminate 50% of a substance in the plasma.
Chemical Subside
A method that involves mixing certain household chemicals in an enclosed space to create toxic gases
Toxidrome
Narcotic, sympathomimetic, sedative-hypnotic, cholinergic, anticholinergic
Drug abuse
Any use of a drug that causes physical, psychological, economic, legal, or social harm to the user or others affected by the user’s behavior
Habituation
Physical and psychological dependance on a drug
Physical dependance
A physiologic state of adaptation to a drug caused by chronic use, usually characterized by tolerance to the effects of the drug and withdrawal if use of the drug is stopped (especially abruptly)
Tolerance
Physiologic adaptation to the effects of a drug such that increasingly larger doses of the drug are required to achieve the same effect.
Withdrawal syndrome
A predictable set of signs and symptoms, usually involving altered CNS activity, that occurs after the abrupt cessation of a drug or after a rapid decrease in the usual dosage of a drug
Drug addiction
Chronic disorder characterized by the compulsive use of a substance that results in physical, psychological, economic, legal, or social harm to the user, the user continues to use the substance despite the harm.
Antagonist
A molecule that blocks the ability of a given chemical to bind to its receptors, preventing a biological response
Potentiation
The enhancement of the effect of one drug by another drug.
Synergism
The action of two substances such as drugs, in which the total effects are greater than the sum of the independence effects of the two substances.
Esophageal Varices
Fluid back up in the hepatic system causes elevated pressures, as pressures continue to rise, smaller vessels leading into the liver can become engorged with blood and swell and can rupture.
Delirium Tremens (DT’s)
48-72 hrs after the last alcohol intake.
Signs and symptoms include confusion, tremors, restlessness, fever, diaphoresis, tachycardia, hypotension secondary to dehydration.
Rhabdomyolysis
The destruction of muscle tissue leading to a release of potassium and myoglobin
Hallucinogen
Substance that can impair judgement, alter the users perception of reality and create a realistic sensation of images or sounds that are not actually present
Barbiturates (sedative hypnotic)
Class of medication that act as a CNS depressant. They have therapeutic uses as anxiolytics, anticonvulsants, and hypnotics.
-Analgesic effects are associated with barbiturate use, but often minimal.
Benzodiazepines (sedative hypnotic)
Most commonly used to treat anxiety, seizures, and withdrawal symptoms.
- Stimulate GABA pathways resulting in sedation and reduced anxiety
- Metabolized by the liver
Narcotics (CNS depressant
Opiate- used to describe various alkaloids derived from the opium or poppy plant (such as morphine and codeine)
Opioid- refers to a synthetic narcotic with sedative prosperities that is not derived from the opium (such as oxycodone, hydrocodone, tramadol, and fentanyl)
Fentanyl is more potent then morphine, it takes less of the medication to create a therapeutic effect.
Morphine has some vasodilatory properties due to histamine release, and fentanyl has a shorter half life.
Antidotes
Beta blocker- IV glucagon 1mg every 5 mins.
Calcium channel blocker- IV calcium chloride or calcium gluconate is the initial treatment, IV glucagon may improve both the pulse rate and myocardial contractility.
Organophosphate poision
Diarrhea
Urination
Miosis (constricted pupils), muscle weakness.
Bradycardia, bronchospasm, bronchorrhea (discharge of mucus from lungs)
Emesis
Lacrimation (excessive tearing of eyes)
Seizures, salvation, sweating
Tricyclic Antidepressant (TCA’s)
Formerly prescribed for depression, may see them prescribed for insomnia, eating disorders, and personality disorders.
- They work as serotonin and norepinephrine reuptake inhibitors.
- Overdose can cause sympathomimetic and serotonergic effects.
- “hot as a hare, blind as a bat, dry as a bone, red as a beet, and mad as a hatter”
Monoamine oxidase inhibitors (MAOI’s)
Used to treat atypical depression.
-norepinephrine, serotonin, and dopamine are primary neurotransmitters that assist with improving mood and affect with there presence in certain cells and circuits in the brain.
Selective Serotonin reuptake inhibitors (SSRI’s)
A common choice for managing depression.
- work by enhancing serotonergic neurotransmission and inhibiting the breakdown of serotonin.
- Few cardiac effects or anticholinergic effects, so they are a safer options to TCA’s
- prozac, paxil, citalopram, zoloft
Serotonin syndrome
Idiosyncratic complication that occasionally occurs with antidepressants therapy.
Signs and symptoms include shivering and diarrhea to muscle rigidity and fever.
Lithium
Common mood stabilizer used in the treatment of bipolar disorder.
