Patho&Pharm Exam 1

Pharmacokinetics

what the body does to a drug (ADME)

Absorption

Route determines the rate of absorption

Distribution

How the drug gets to where it's supposed to act 

-Drug movement: blood → tissues

• Unbound- drug chemicals that are not bound to by proteins

  • Low dose

• Bound- proteins binding onto drug chemicals/ lowers distribution

  • High dose

Metabolism

breaking down compounds to get rid of drugs

• Inactivates chemical compounds to make them ineffective

• Prevents toxicity

• CYP450 enzymes: Liver enzymes that metabolize drugs

First-pass effect:

some drugs have a high first-pass effect: get absorbed through the gut and go to the liver first before circulation, making them inactive

• Requires higher dose to reach target without being broken down

• Metabolism

Excretion

removal of drugs through the kidneys (commonly)

Pharmacodynamics

How drugs produce effects in the body

• Drug response

• Dose and response

• Goal

Neurogenic Shock (T4 Traumatic SCI)

Etiology	Trauma severs the spinal cord at T4, disrupting thoracolumbar sympathetic outflow
Pathogenesis	Below injury: Sympathetic signals to heart (B1) + vasculature (a1) lost/ not stimulated Vagal (muscarinic) output to SA node unaffected (exits above cord, now unopposed (PNS)
Manifestations	Hypotension (low A1 tone) Bradycardia → unopposed vagal nerves Warm/dry skin → low sympathetic vasoconstriction, high parasympathetic vasodilation (vs. cold/clammy hypovolemic shock)