Module 2- Chapter 5 Flashcards
agonist
**Allows receptor effect
If the key turns the lock the drug is said to be an agonist
**An agonist excites the receptor, so the key “fits”___the knob turns (an action occures
antagonist
***Blocking receptor effect
if the drug occupies the lock but doesn’t “turn it” it is said to be an antagonist.
Antagonist in activates the receptor by occupying and blocking the “keyhole” the real key won’t insert, the knob doesn’t turn, and no “drug/hormone” action occures
Heroin - Agonist or antagonist? side effect?
is the agonist, a specific effect (analgesia…and respiratory failure in high doses)
Naloxone (Narcan)
in the ED is given as an opioid receptor antagonist to “reverse” the effects of an opioid overdose
Local effects
are like the effects of nasal sprays and topical creams, that are largely limited to the site of administration and surrounding tissues.
***side effects and toxicity are generally much less
Local drug side effects examples
Latisse can cause skin darkening around the eyes as well as eye irritation, dryness or the eyes and redness of the eyelids.
- Topical antibiotics for skin infections
- Mouthwashes with antibacterial agents to treat dental infections
Corticosteroids - local side effects?
systemic side effects?
Local effects - hoarseness of the voice
Systemic side effects - weight gain and adrenal gland suppression
systemic effects examples:
occur from oral, inhaled and parenteral absorption in which the drug is “felt” to varying degrees, throughout the body.
*Oral antibiotics for treatment of pneumonias, meningitis and kidney infections
Prednisone
Oral - Systemic effects
use to treat a case of poison ivy
All drugs
have side effects
Side effects
***untoward effects
are unintended consequences of giving a drug
using a side effect as a therapeutic effect for a different condition
Narcotics - cause constipation
this could be used for diarrhea
Antihistamines - cause sedation
this could be used for insomnia
Drugs side effects can be
mild, temporary, moderate and annoying
Adverse Effects
***significant untoward effect
are severe side effects
aspirin-like Vioxx - cause what effects?
was taken off the market due to unacceptable cardiovascular toxicity - Adverse effects
Accutane
is so dangerous (birth defects) - Adverse effects
still on the market for treating severe cystic acne
T.I
Therapeutic index
High T.I when the toxic dose (lethal dose) is much greater than the therapeutic dose
A lower T.I means there is little room for dosing errors.
Toxic Effects
All drugs become toxin at high enough blood levels.
Worse than “Side Effects “ and “Adverse Effects “ are Toxic Effects
Toxic Effects examples
Aminoglycosides - may cause Ototoxicity (hearing loss)
Nephrotoxicity - kidney damage
Vancomycin - may cause “redman syndrome” itching, flushing, swelling
Metformin - may cause Lactic acidosis
How to prevent “Toxic Effects” ?
the appropriate use of drugs
Idiosyncratic Reactions
are those which do not involve any of the known pharmacological effects of drug and do not occur in most humans or animals.
***Atypical, unpredicctable and DO NOT involve immune mechanisms.
***are not “allergies”
Idiosyncratic Reactions example
sedative-hypnotic drug, which is often given to treat seizure, were itself to cause a seizure.
Synergistic
Positive drug - drug interactions
Synergism
drug A + drug B =an exaggerated effect (2 + 2=> 4) more than expected
Additive effect
What is expected ( 2 + 2 = 4)
Example of the drug interaction known as “synergism”
Tylenol and codeine - analgesics work together to produce a better pain relief
Alcohol and tranquilizers - Synergistic
propofol (white stuff) and Valium - use to induce general anesthesia
Drug “effects” may be
Additive (1 + 1 = 2) what you expected
Synergistic (1 + 1 = 3) more than expected
Negative (1 + 1 = 1) less than expected
opioid pain patch (Duragesic)
designed to release the drug over 3 days. The heated waterbed caused the drug to be released too quckly and killed the man.
Negative drug
drug interactions occur where the effect of one drug (or food) interferes or alters the effects of another.
Allergic Reactions
is an antigen/antibody immune system reaction and is usually accompanied by the release of histamine.
Example of allergic Reactions
Develop a rash
Experience bronchoconstriction
undergo a drop in blood pressure
anaphylactic reactions
the very worst kind of allergic reactions which cause edema and impair breathing - lead to shock and even death
The 5 “Rights” of medication safety
Right person Rights medication Right dose Right time Right route
Aminoglycosides - cause? what effect (side effect, adverse or toxin?
Toxin effect - may cause Ototoxicity (hearing loss)
Nephrotoxicity – cause? what effect (side effect, adverse or toxin?
Toxin effect - may cause kidney damage
Vancomycin -cause? what effect (side effect, adverse or toxin?
Toxin effect - may cause “redman syndrome” itching, flushing, swelling
Metformin-cause? what effect (side effect, adverse or toxin?
Toxin effect - may cause Lactic acidosis
