Drug Interactions (Desai) Flashcards
What are 4 types of adverse drug reactions?
- Idiosyncratic
- Toxic (overdose)
- Allergic
- Incompatible/Interaction/Side effect
What is a reaction to a drug that is opposite its effect, (e.g. patient is agitated after getting a sedative)?
Idiosyncratic reaction
What is the term for too much of a drug, too soon that will manifest in CNS, kidneys, liver, cardiovascular, or respiratory?
Drug overdose (toxicity)
What are 4 factors that can lead to patient overdose on drug?
- Age
- Body weight
- Debilitating systemic disease
- Genetic predisposition
When dealing with adverse drug reactions, which of the following factors is most important: age, body weight, debilitating systemic disease, or genetic predisposition?
Body weight
What are 3 causes of drug overdose in a dental practice?
- Total dose administered is excessive
- Intravascular injection
- Abnormal rapid absorption
What systemic problem can lead to drug overdose?
Slow renal drug elimination
What is the maximum dose of Lidocaine in a healthy patient?
3.2mg/lb, maximum 500mg
What is max number of 2% Lido carpules you can give to not exceed the 500 mg maximum?
500mg x (1carpule / 36mg) = 13 carpules
What is lidocaine’s effect on the heart?
Decreases automaticity. It slows it (lido is an ER drug used to control atrial fibrillation)
What are 2 causes of a patient getting an overdose even though correct dose was administered?
- intravascular injection
2. Rapid uptake and distribution
What is the standard of care to avoid intravascular injection of local anesthetic?
Aspirate before injection, in 2 different planes
What are signs of local anesthetic overdose?
- Confusion
- Talkative
- Tremor
- Nystagmus
- Elevated vital signs
In a local anesthetic overdose there will be stimulation followed by depression resulting in what type of seizure?
Tonic-clonic seizure resulting in loss of respiration
What is emergency drug for seizures?
10mg of Valium IV
What is the maximum dose of Epinephrine in a healthy patient?
.2mg
What is the amount of epi in 1:100,00 solution?
.01mg/mL = .018 mg / carpule
What is the maximum number of carpules of 1:100,00 epi to get to the maximum epi dose of .2mg?
11 carpules 1:100,000 epinephrine
What is the maximum dose of epi for patients with cardiovascular disease?
.04mg
What is the maximum dose of Levonordephrine?
1.00 mg in health
.2 mg for cardiac disease patient
Levonordephrine comes in what concentration?
1:20,000 = 0.5mg/mL = 0.9 mg/1 carpule
What is the maximum number of carpules to get to max amount 1:20,000 Levonordephrine?
11
What is the proper management of an epinephrine overdose?
- Reassure pt
- Oxygen
- Vitals
- Inform it should stop in 1-3 mins
A type I allergic reaction has what character and what mediates it?
Immediate
IgE mediates causing histamine release from Mast Cells
A type 2 allergic reaction has what character and what mediates it?
Cytotoxic response due to Antigen-Antibody complex activating cytotoxic cells. IgM/IgG-Ab complex mediated.
Anaphlaxis and urticaria are what type of allergic reactions?
Type I, IgE mediated
Transfusion reactions and Goodpasture’s syndrome are what type of allergic reactions?
Cytotoxic with IgM/IgG-Ab activating cytotoxic cells
Goodpasture’s syndrome is an autoimmune problem where IgG/IgM-Ab complexes activatie cytotoxic cells in Type II response, but antibodies attack what?
Lung and Kidneys
What must occur before a type I allergic reaction?
Must be sensitized by allergen binding IgE causing Il-4 to make B-cells produce IgE antibodies for that antigen
What are 5 things mast cells / basophils release when antigen binds the IgE attached to the cell surface?
- Histamine
- Cytokines
- Interleukins
- Leukotrienes
- Prostaglandins
Vasodilation in a Type I IgE mediated hypersensitivity reaction results in what?
Anaphylaxis, rash
Edema in a Type I IgE mediated hypersensitivity reaction results in what?
Urticaria (hives), angioedema, laryngeal edema
Mucous secretions in a Type I IgE mediated hypersensitivity reaction results in what?
Rhinorrhea
Nerve stimulation in a Type I IgE mediated hypersensitivity reaction results in what?
Itching
An immediate allergic reaction usually occurs within what time period?
Within 60 min of exposure to antigen
What is the first thing to do when not allergic reaction? (Not sure what this question means)
Call 9-1-1
What are 3 things done to manage allergic reaction while 911 is called?
- Administer oxygen, take vitals, give 1:100 Epi 0.3 mg IM or Subcutaneous
- O2, vitals, 50mg Benedryl IM
- O2, vitals, 100mg Solucortef IM (corticosteroid)
What is the timeframe for a delayed allergic reaction?
More than 60 minutes
What is an oral antihistamine for management of delayed allergic reaction?
Diphenhydramine (Benedryl), 50 mg, qid, for 24 to 48 hrs. If symptoms worsen get to ER.
What is the term for an overdose of a drug that injures a physiologic system?
Toxicity
What is the term for an expected or predictable undesirable effect of a drug that occurs at therapeutic doses?
Side effect
What is the term for the presence of one drug effects the pharmacodynamics (absorption, distribution, metabolism, excretion) of another drug?
Drug-drug interaction
What is the term for when the presence of a drug alters the body’s physiology, leading to a harmful condition (may overlap with the concept of side effect)
Drug-physiology interaction
What is the term for when a drug will alter laboratory test results without impacting the physiologic system being measured - essentially a false-positive or a false-negative laboratory test result?
Drug-laboratory test interaction
What is the term for when a drug triggers an immunologic response?
Allergic reaction
What is the term for when a drug creates a physiologic or psychological response that is unpredictable and is unique to the individual?
Idiosyncratic reaction
