Test 1 Study Guide

Question 2

What are the benefits of transdermal application?

Answer 2

• No peaks and valleys
• More compliance
• Lasts 3 days
• Avoids first pass
• Low side effects

Transdermal application allows for steady drug delivery and minimizes side effects.

Question 3

Define biophysics in relation to drug concentration.

Answer 3

Concentration of drug in plasma AND drug concentration at site of action (effect site is biophase)

Biophysics examines the physical principles underlying drug action and distribution.

Question 4

Explain enterohepatic recirculation and its impact on antibiotics and birth control pills.

Answer 4

All drugs absorbed from GI tract must go thru liver; some drugs undergo extensive metabolism. If EHRC is blocked by antibiotics, birth control pills are excreted more rapidly.

Enterohepatic recirculation can prolong the action of certain drugs.

Question 5

What is the GPCR pathway?

Answer 5

GPCRs are 7-transmembrane receptors that activate intracellular G proteins (Gα, Gβ, Gγ). Ligand binding activates downstream effectors like adenylyl cyclase or phospholipase C.

This pathway generates second messengers such as cAMP.

Question 6

Explain the NMDA receptor pathway.

Answer 6

The NMDA receptor is a ligand-gated ion channel requiring glutamate and glycine binding, and depolarization to open.

It is crucial for synaptic plasticity and memory function.

Question 7

What is the primary action of Ventolin?

Answer 7

Smooth muscle dilation via β2 adrenergic receptor activation.

Ventolin is commonly used to relieve bronchospasm in conditions like asthma.

Question 8

List at least four factors that affect drug absorption.

Answer 8

• Route
• Solubility
• Conditions at the site
• Ionization
• Bioavailability

These factors significantly influence how effectively a drug is absorbed into the bloodstream.

Question 9

What is the first pass effect of the lungs?

Answer 9

Percentage of drug taken up by the lungs after IV drug administration; influences arterial plasma concentration.

The lungs can uptake 65-70% of the initial drug dose, which affects dosing profiles.

Question 10

What is the definition of bioavailability?

Answer 10

Fraction of drug that reaches systemic circulation, mainly for PO drugs.

It indicates how much of the drug is available for therapeutic effect.

Question 11

What are the consequences of stopping metoprolol before surgery?

Answer 11

Hypertensive and tachycardia due to receptors not blocked.

This can lead to increased cardiovascular risk during surgery.

Question 12

What is LD50?

Answer 12

Dose that produces death in 50% of the population.

It is a standard measure of acute toxicity.

Question 13

What is the difference between metabotropic and ionotropic receptors?

Answer 13

Metabotropic: slow responses, GPCR; Ionotropic: rapid response, binding site and channel combined.

This distinction is crucial for understanding receptor pharmacodynamics.

Question 14

What is the role of epinephrine in local anesthetics?

Answer 14

Slows absorption and prolongs duration.

Epinephrine is often added to local anesthetics to enhance their effects.

Question 15

What is ion trapping?

Answer 15

The phenomenon where drugs accumulate in one compartment due to pH differences affecting their ionization.

This can influence drug efficacy and toxicity.

Question 16

What are the weak acids and weak bases among anesthesia drugs?

Answer 16

Weak acids: Barbiturates, propofol, acetaminophen; Weak bases: Local anesthetics, opioids, benzodiazepines, vasopressors.

Understanding the acid-base characteristics is important for drug interactions.

Question 17

What happens during upregulation and downregulation of receptors?

Answer 17

Upregulation increases receptor numbers; downregulation decreases them in response to drug exposure.

This mechanism can affect drug efficacy and tolerance.

Question 18

What is the therapeutic index?

Answer 18

LD50/ED50; a measure of drug safety.

A higher therapeutic index indicates a safer drug profile.

Question 19

What medications are associated with extensive first pass effect?

Answer 19

• Warfarin
• Lidocaine
• Metoprolol
• Inderal

These medications may require careful dosing and monitoring.

Question 20

What are the effects of agonist-antagonist medications on pain control?

Answer 20

Agonists may have antagonist activity, decreasing the effect of full agonists, leading to more pain meds needed.

This can complicate pain management in surgical settings.

Question 21

What are the characteristics of the Na/K pump?

Answer 21

An example of active transport that uses ATP/energy.

This pump is vital for maintaining cellular ion balance.

Question 22

What is the Emax of ketamine?

Answer 22

The maximum efficacy of ketamine when bound to its receptor.

Understanding Emax helps in determining appropriate dosing for therapeutic effects.

Question 23

What are the effects of ionization and lipid solubility on drug absorption?

Answer 23

High lipid soluble drugs are hydrophobic, nonionized, and pass cell membranes more easily.

This affects how drugs are formulated and administered.

Question 24

What is the IM dose of Atropine?

Answer 24

0.01-0.02 mg/kg

Atropine is used to increase heart rate in bradycardia.

Question 25

What is the IM dose of Succinylcholine for pediatric patients?

Answer 25

4-5 mg/kg ## Footnote Succinylcholine is a neuromuscular blocker used for rapid sequence intubation.

Question 26

What is the IM dose of Ketamine for sedation?

Answer 26

3-5 mg/kg ## Footnote Ketamine is an anesthetic agent that provides dissociative anesthesia.

Question 27

What is the purpose of Methergine?

Answer 27

Treatment of postpartum hemorrhage ## Footnote Methergine should not be given IV.

Question 28

What is the IM dose of Methergine?

Answer 28

0.2 mg ## Footnote Methergine is contraindicated in patients with hypertension.

Question 29

What are the contraindications for Methergine?

Answer 29

* Hypertension * Coronary vasospasm * Bronchospasm ## Footnote Methergine can cause significant side effects in patients with these conditions.

Question 30

What is the initial IM dose of Hemabate?

Answer 30

1 mL (250 mcg Hemabate) ## Footnote Hemabate is also used for the treatment of postpartum hemorrhage and is contraindicated in asthmatics.

Question 31

Which medications are only given IM?

Answer 31

* Methergine * Hemabate ## Footnote These medications should not be administered IV.

Question 32

Which medications can be given IM if you need to?

Answer 32

* Atropine * Succinylcholine * Ketamine ## Footnote These medications can be administered via the IM route based on clinical indications.

Question 33

True or False: Methergine can be given IV.

Answer 33

False ## Footnote Methergine should only be administered via the IM route.

Question 34

True or False: Hemabate is contraindicated in asthmatics.

Answer 34

True ## Footnote Hemabate can cause bronchospasm in asthmatic patients.

Question 35

What is the primary advantage of intrathecal administration?

Answer 35

Bypasses the blood-brain barrier ## Footnote Intrathecal administration allows for direct delivery into the cerebrospinal fluid (CSF), avoiding systemic circulation.

Question 36

What types of substances can be administered intrathecally?

Answer 36

Locals and opioids ## Footnote These include local anesthetics and opioid medications used for pain management.

Question 37

What does high lipid solubility imply about a substance's ability to pass through cell membranes?

Answer 37

Hydrophobic, nonionized, lipophilic, no charge, nonpolar ## Footnote High lipid solubility facilitates easier passage through cell membranes due to compatibility with the lipid bilayer.

Question 38

Fill in the blank: High lipid soluble substances are typically _______.

Answer 38

nonionized ## Footnote Nonionized substances are more likely to diffuse across cell membranes.

Question 39

What does LD50 represent?

Answer 39

Dose that produces death in 50% of the population ## Footnote LD50 is a standard measure used in toxicology to assess the acute toxicity of a substance.

Question 40

Define ED50.

Answer 40

Effective dose for 50% of the population to obtain 50% therapeutic effect ## Footnote ED50 is commonly used to determine the dosage of a drug that is effective in half of the population.

Question 41

What is Emax?

Answer 41

Efficacy; the measure of the magnitude of the effect once the drug is bound ## Footnote Emax indicates the maximum effect achievable by a drug.

Question 42

What does the therapeutic index indicate?

Answer 42

LD50/ED50; safety of the drug ## Footnote A higher therapeutic index indicates a safer drug with a wider margin between effective and lethal doses.

Question 43

Name a drug associated with voltage-gated ion channels.

Answer 43

Amlodipine, Cardizem, Cardene ## Footnote These drugs are calcium channel blockers that affect cardiac and smooth muscle contraction.

Question 44

Which receptors are associated with GPCR?

Answer 44

Adrenergic Receptor, Muscarinic ## Footnote Adrenergic receptors include phenylephrine, epinephrine, norepinephrine, albuterol, and dexmedetomidine.

Question 45

List some drugs that act on GABA receptors.

Answer 45

Propofol, etomidate, versed, methohexital ## Footnote These drugs are commonly used as anesthetics and sedatives.

Question 46

What is the difference between metabotropic and ionotropic receptors?

Answer 46

Metabotropic: slow responses, GPCR; Ionotropic: rapid response, postsynaptic ## Footnote Metabotropic receptors rely on second messengers, while ionotropic receptors facilitate immediate ion channel opening.

Question 47

Fill in the blank: Orthosteric binding occurs at the _______.

Answer 47

[same site] ## Footnote Orthosteric sites are the primary binding sites where endogenous ligands interact with receptors.

Question 48

What are the effects of allosteric binding?

Answer 48

Positive: increases agonist affinity; Negative: decreases agonist affinity | multiple binding sites ## Footnote Allosteric modulators can enhance or inhibit the effect of the primary ligand at the receptor.

Question 49

Describe the conformation change theory.

Answer 49

Alteration in the shape of a protein due to ligand or substrate binding ## Footnote This theory explains how binding events can influence the function of proteins, such as receptors and enzymes.

Question 50

What is the impact of agonist-antagonist medications on pain control during surgery?

Answer 50

More pain meds needed; agonists may also have antagonist activity ## Footnote Agonist-antagonist medications can reduce the effectiveness of full agonists, thus requiring higher doses for pain control.

Question 51

Name two examples of opioid agonist-antagonists.

Answer 51

Butorphanol, nalbuphine ## Footnote These medications can provide pain relief while minimizing side effects like respiratory depression.