midterm

Pharmacokinetics

Pharmacokinetics

what the body does to the drug (absorption, distribution, metabolism, and excretion)

therapeutic classification

based on their usefulness in treating a particular disease

Pharmacodynamics

what the drug does to the body

the biochemical effects and physiological effects of drugs and the mechanisms by which those effects are produced

four basic pharmacokinetic processes

• absorption

• distribution

• metabolism

• excretion

what is the primary factor in determining length of time for effect of drugs to occur?

absorption: the more rapid the absorption, the faster the onset

what are 4 different ways a drug can be absorbed?

• passive diffusion

• facilitated diffusion

• endocytosis

• active transport

distribution

the transport of drugs throughout the body

what is the simplest factor for determining distribution of medication?

amount of blood flow to body tissues

drugs exist in what 2 forms?

• free drug molecules

• drug-protein complex

where does drug metabolism take place?

in the liver: the body’s chemical processing plant

metabolism

drugs are broken down by the liver by liver enzymes

elimination

remaining drug metabolites in the bloodstream are filtered by the kidney. a portion is reabsorbed into the bloodstream, and the remainder is excreted out of the body

therapeutic range

plasma drug concentration between the minimum effective concentration and the toxic concentration

loading dose

if there is not enough time to build up a drug to the therapeutic range, a loading dose is given, which is a bigger dose upfront

what do stimulant laxatives do?

stimulates the bowels (increase muscle contraction)

what do bulk-forming agents do?

absorb liquid in the intestines and swell to form a soft, bulky stool

what do stool softeners / surfactants do?

increases the amount of water and fat that stool absorbs

what do osmotic laxatives do?

draw water into the stool, resulting in softer stools

what is a possible adverse effect of Metamucil?

with insufficient water, it may cause obstructions in the intestines

what is important to know before giving a laxative?

if the cause of constipation is a blockage, then a laxative will do more harm than good D:

what cause of nausea do serotonin receptor antagonists treat?

nausea from chemo/surgery

what drug terminates acute angina episodes?

nitroglycerin

how do nitrates work?

relaxes both arterial and venous smooth muscle; dilate coronary arteries

WHICH

reduces the hearts workload and lowers oxygen demand

what are the potential adverse effects of nitroglycerin? (4)

• hypotension

• dizziness

• headache

• flushing of face

What should you teach a patient for using Nitroglycerin at home? (5)

• take one tablet every 5 minutes until pain is relieved.

• do not take more than 2 doses, and call EMS of chest pain is not relieved.

• place SL tab or spray under tongue.

• lie down before taking.

• wait 24 hours before taking sidenafil or a phosphodiesterase-5 inhibitor (viagra lol)

How do beta blockers work?

reduce the cardiac workload by slowing heart rate and reducing contractility.

what are the potential adverse effects of beta blockers? (5)

• fatigue

• drowsiness

• bradycardia

• insomnia

• confusion

how do calcium channel blockers work?

inhibit the transport of calcium into myocardial cells, and relaxes arteriolar smooth muscle

this reduced cardiac workload and brings more O2 into the myocardium

what are potential adverse effects of calcium channel blockers? (5)

• hypotension

• bradycardia

• constipation

• headaches

• dizziness

what should the nurse do for a patient taking calcium channel blockers? (4)

• hold medication if HR is 60 or less.

• obtain BP.

• obtain daily weights.

• assess bowel function.

how do diuretics lower blood pressure?

increases urination > decreases blood volume > decreases blood pressure

what are possible adverse effects of potassium-sparing diuretics? (3)

• hyperkalemia (too much potassium)

• gynecomastia (man boobs)

• dysrhythmias

what is the mechanism of action for loop diuretics?

inhibits the reabsorption of salts in the kidneys

what are potential adverse effects of loop diuretics? (4)

• hypokalemia

• postural hypotension

• dehydration

• ototoxicity

what should be monitored with patients taking diuretics? (3)

• potassium levels

• electrolyte levels

• blood glucose and uric acid levels

how do calcium channel blockers decrease blood pressure?

block calcium ion channels > cause vasodilation > decreases BP

what is important to know about calcium channel blockers?

cannot consume grapefruit juice!! it will cause the medication to release very fast and may cause an overdose

what is the mechanism of action for ACE inhibitors?

reduces angiotension II (vasoconstrictor) and aldosterone level to lower BP

what are potential adverse effects of ACE inhibitors? (4)

• orthostatic hypotension

• first dose effect (rapid drop in BP)

• fetal toxicity

• angioedema (swelling of lips/mouth)

what is a common side effect of ACE inhibitors?

dry cough

what is important to know about ACE inhibitors? (3)

• cannot consume grapfruit juice

• first dose may cause rapid drop in BP

• adverse effect of angioedema (watch for swelling in mouth)

how do angiotensin II receptor blockers (ARBs) lower blood pressure?

blocks the effect of angiotensin II (a chemical that narrows blood vessels)

how do beta-adrenergic blockers decrease blood pressure?

decreases heart rate and contractility (force)

what do ACE inhibtors do to treat heart failure?

reduce afterload by decreasing blood pressure and reducing blood volume (dilates veins)

how do beta-adrenergic blockers treat heart failure?

they have an inotropic effect, so they decrease heart contractility, therefore reducing the workload of the heart

what should be monitored in patients taking diuretics for heart failure? (3)

• monitor sodium intake

• weight loss

• fatigue and muscle cramps

how do cardiac glycosides treat heart failure?

increases force of heartbeat, slows heart rate, which increases efficacy of heart muscle

what are potential adverse effects of cardiac glycosides? (3)

• neutropenia (low WBCs)

• dysrhythmias

• digoxin toxicity

what are symptoms of digoxin toxicity? (4)

• problems with NS

• nausea + vomiting

• confusion

• visual disturbances

what should patients be taught when taking cardiac glycosides? (4)

• know signs/symptoms of toxicity

• monitor pulse rate

• report weight gain

• eat foods high in potassium (low K+ = more at risk for toxicity)

what are the types of lipoproteins, and which is good / bad?

• high-density lipoprotein (HDL)

  protective effect against CVD

• low-density lipoprotein (LDL)

  associated with CVD

REMEMBER: LDL = LOUSY, HDL = HERO

what do HMG-CoA reductase inhibitors (statins) do?

reduce serum-lipid levels

what are potential adverse effects of HMG-RoA reductase inhibitors? (statins) (4)

• headache

• muscle or joint pain

• heartburn

• rhabdomyolysis (sign = muscle pain)

what is important to remember about statins? (4)

• can interact with other meds + grapefruit

• monitor liver function tests

• do not use when pregnant or breastfeeding

• watch for signs of GI upset

what does nicotinic acid do?

reduces triglycerides and increases HDL levels

what are potential adverse effects of nicotinic acid? (6)

• flushing

• hot flashes

• excess gas

• diarrhea

• heptatotoxicity

• gout

what should be monitored in patients taking nicotinic acid? (3)

• liver function

• uric acid levels (gout)

• blood-sugar levels

what medication class treats inflammation with asthma? (4)

• glucocorticoids

• mast cell stabilizers

• leukotriene modifiers

• monoclonal antibodies

what medication class treats bronchospasm with asthma? (3)

• beta-adrenergic agonists

• methlyxanthines

• anticholinergics

what is the dominant receptor for smooth muscle relaxation at the lungs, blood vessels, gi tract, and liver?

beta 2

what is the dominant receptor for adipose tissue and the bladder?

beta 3

what do beta-adrenergic agonists do for asthma?

relieves bronchospasms by opening the airway by relaxing the smooth muscle of the bronchi

what do glucocorticoids do for asthma?

supress airway inflammation

what is an important teaching for patients using glucocorticoid inhalers?

always rinse mouth after use, because it can cause infection of the mouth/nose

how do anticholinergics work?

Anticholinergics block acetylcholine from binding to its receptors on certain nerve cells. They inhibit parasympathetic nerve impulses, which are responsible for involuntary muscle movements

what do methylxanthines do?

it is a bronchodialator, so it opens the airway

what medication dampens the cough reflex?

antitussives

how do antihistamines work?

block / inhibit H1 receptors

what are drugs that inhibit H1 (histamine) receptors used to treat?

allergic reactions

what type of antibiotics are patients usually started on?

broad spectrum -targets lots of bacteria

what are possible adverse effects of antibiotics? (3)

• destruction of normal gut flora (causes diarrhea).

• suprainfection - infection with a second, resistant organism.

• allergy (most common with penicillins).

what are teaching points for patients taking antibiotics? (4)

• complete full dose.

• take missed dose asap.

• signs + symptoms of hypersensitivity.

• may need a backup method of birth control.

pharmacologic classification

based on the way the drug works at the molecular, tissue, and body systems level

anticoagulants, antihhyperlipidemics, and antiarrhythmics are examples of what type of drug classification?

therapeutic classification

diuretics, vasodilators, and ACES are examples of what type of drug classification?

pharmacologic classification

what is the basic formula of the formula method?

desired dose / dose on hand X quantity = x (amount to give)

• D/H X Q = x