Lecture 4 Flashcards
Dermal Route Exposure
Has one barrier.
Respiratory Route Exposure
Has two barrier
Oral Route Exposure
Might have two, but the first barrier is not much of a barrier to speak of.
Parenteral routes
NO BARRIERS
Intravenous (IV)(Most direct)
Intramuscular (Vaccines)
Intraperitoneal (Stomach area injection)
Subcutaneous (Insulin)
Isoniazid
Anti tuberculosis medication
Acute
<24 Hrs. Single exposure
Subacute
Less than a month. Repeated Exposure
Subchronic
1-3 months
Chronic
more than 3 months, up to years
Timed dosing
Ex taking 3 pills a day
Continuous Dosing
Infusion IV at hospital
Reversible Toxic Effects
Most of the time it is reversible, as the drug clears from the system we go back to how we were.
Irreversible Toxic Effects
No way to go back
Irreversible with Repair Toxic Effects
The only was to go back is to introduce new molecules
Immediate Toxicity
Side Effects can be seen almost immediately (Skin irritation or Mucosae (stomach lining or respiratory lining) irritation) (LOCAL TOXICITY)
Delayed Toxicity
Delayed health effects may take months or years to appear (Ex cancer takes a long time to develop) (SYSTEMIC TOXICITY)
Tolerance
Decreased response to xenobiotic with repeated
exposures.
Additive
2+2=4 Drugs add to each other so you would experience the effects of both.
Synergistic
2+2=20 Drugs enhance each other. when the combined effect is greater than the sum of each independently
Potentiation
0+2=10. When a drug alone will have no effect, however when combined the effects will be enhanced.
Anatgonism
2+2=1 or 2+0=1. when the combined effect is less than the sum of each independently
pKa value meaning
determines an acid’s strength
Acidic drugs will dissolve _____ in the __________.
Better, stomach
Neutral drugs will dissolve _________ in the ________.
Better, small intestine.
Idiosyncratic Toxicity
- Characterized by extreme
sensitivity or insensitivity. - Considered an “abnormal”
response. - Often genetically mediated.
- One type is the “allergic” or
“sensitization” reaction:
– Immunologically mediated.
– Threshold with steep dose-response
Differences between genders are
generally due to?
Hormonal activity
Mechanism is often due to differential
induction of
metabolism
Tablet Dosage Forms
– Most commonly used oral dosage form.
– Must overcome the reduction in effective surface area produced during the compression
process
Capsule Dosage Forms
– In theory a very efficient dose form
Suspension Dosage Forms
A suspension of a finely divided powder will maximize the potential for rapid dissolution
Solution Dosage Forms
In most cases absorption is rapid and complete. Rate limiting step is often the rate of gastric
emptying.
