Week 3 Flashcards
Drugs lack specificity therefore they can?
Act on many different organs and tissues
Due to the lack of specificity they can cause an?
Adverse reaction
Every drug has more than one
Action
Therapeutic effect equals?
Desirable action
Adverse effect equals
Undesirable action
What is dependant on the indication for which the drug is being used for
The effect
What are the adverse drug reaction categories? (5)
Toxic reaction
Side effect
Idiosyncratic reaction
Drug allergy
Interference with natural defense mechanism
Describe toxic reaction
It is extension of the effect on target organ
- it is dose related, predictable and excessive of desired effect
Describe side effect
Non therapeutic action on non target organs
-dose related
-predictable reaction
(Ex. Advil causing upset stomach)
Describe idiosyncratic reaction
Genetically related abnormal response
-neither side effect nor allergic reaction
Describe drug allergy
Immunological response
-mild to severe (rash-anaphylaxis)
-not predictable and not dose related
Describe interference with natural defense mechanism
Reduces body’s ability to fight infection
One must assess what prior to drug use
Risk to benefit ratio
What does teratogenic mean
Producing a malformed fetus
Why is the dental hygienist to question for pregnancy
Because the highest risk from exposure to drugs occurs BEFORE knowing the pregnancy status
What are some dental drugs that are safe for pregnancy
Penicillin
Erythromycin
Acetaminophen
Lidocaine
What are some dental drugs that are contraindicated for pregnancy
Tetracycline
Benzodiazepines
Metronidazole
Non-steroidal anti inflammatory
Injectable drugs at site of injection can cause?
Irritation
Pain
Tissue necrosis
Topical agents can cause?
Irritation
Oral drugs can cause a?
GI (gastrointestinal) irritation or dyspepsia (indigestion)
Drug interaction are not adverse effects but can lead to
Adverse effects
Drug interaction can lead to
Toxicity and lack of efficacy
Risk of interaction of drugs increases with?
The number of drugs taken
What role may grapefruits play in drug interaction? (Drug-food)
Eating grapefruits can cause an increase in plasma levels of antibiotics, benzodiazepines, calcium channel blockers and warfarin
Uncontrolled hypothyroidism can increase the sensitivity to? (Drug-disease)
Epinephrine
What is the effect of anticonvulsants on drug metabolism? (Drug-drug)
They decrease drug metabolism therefore increase the plasma level of the drug
There are how many types of hypersensitivity (allergic reactions)
4
Describe type 1 allergic reaction
Anaphylactic; immediate
-mediated by immunoglobin E (IgE) antibodies
Describe type 2 allergic reaction
Cytotoxic; cytolytic
-complement dependant reactions with IgG or IgM antibodies
Describe type 3 allergic reactions
Immune complex
-aggregation of antigens and antibodies
Describe type 4 allergic reaction
Delayed
-mediated by sensitized T lymphocytes and macrophages
In type 2 allergic reaction antigen-antibody complex is attached to red blood cell resulting in
Lysis
Type 3 allergic reaction (immune complex) develops how many days after exposure and be chronic if continual exposure?
4-10days
Describe ED50
Median effective dose
-produces a response in half of the subjects
Describe LD50
Median lethal dose
-kills half of the subjects
What is the equation for therapeutic index
LD50 /ED50 = therapeutic index (TI)
The smaller the TI (narrow TI) what is more likely?
Toxicity is more likely
Larger the TI (wider TI) is?
Safer
