Drugs with MOAs

Question 1

Define the class and mechanism of action of sertraline.

Answer 1

SSRI (selective serotonin reuptake inhibitor)

binds to SERT (serotonin reuptake transporters) to increase the length of time serotonin is available in the synaptic cleft.
Also causes desensitization of 5HT-1A receptors on the presynaptic neuron’s dendrites.

Question 2

Define the class and mechanism of action of fluoxetine

Answer 2

SSRI (selective serotonin reuptake inhibitor)

binds to SERT (serotonin reuptake transporters) to increase the length of time serotonin is available in the synaptic cleft.
Also causes desensitization of 5HT-1A receptors on the presynaptic neuron’s dendrites.

Question 3

Define the class and mechanism of action of citalopram

Answer 3

SSRI (selective serotonin reuptake inhibitor)

binds to SERT (serotonin reuptake transporters) to increase the length of time serotonin is available in the synaptic cleft.
Also causes desensitization of 5HT-1A receptors on the presynaptic neuron’s dendrites.

Question 4

Define the class and mechanism of action of trazodone.

Answer 4

SSRI (selective serotonin reuptake inhibitor)

binds to SERT (serotonin reuptake transporters) to increase the length of time serotonin is available in the synaptic cleft.
Also causes desensitization of 5HT-1A receptors on the presynaptic neuron’s dendrites.

Question 5

Define the class and mechanism of action of escitalopram.

Answer 5

SSRI (selective serotonin reuptake inhibitor)

binds to SERT (serotonin reuptake transporters) to increase the length of time serotonin is available in the synaptic cleft.
Also causes desensitization of 5HT-1A receptors on the presynaptic neuron’s dendrites.

Question 6

What are SSRI’s used to treat?

Answer 6

depression (MMD and bipolar)

obsessive compulsive disorder

panic disorder

Question 7

Define the class and mechanism of action of protripytline.

Answer 7

Tricycline Secondary Amine Antidepressant

Is a non-selective NET inhibitor (also blocks SERT, sodium channels, muscarinic receptors, and histamine 1 receptors)
- the secondary amine in these is what gives it selectivity for NET

Question 8

Define the class and mechanism of action of nortriptyline.

Answer 8

Tricycline Secondary Amine Antidepressant

Is a non-selective NET inhibitor (also blocks SERT, sodium channels, muscarinic receptors, and histamine 1 receptors)
- the secondary amine in these is what gives it selectivity for NET

Question 9

Define the class and mechanism of action of desipramine.

Answer 9

Tricycline Secondary Amine Antidepressant

Is a non-selective NET inhibitor (also blocks SERT, sodium channels, muscarinic receptors, and histamine 1 receptors)
- the secondary amine in these is what gives it selectivity for NET

Question 10

Define the class and mechanism of action of maprotiline.

Answer 10

Tricycline Secondary Amine Antidepressant

Is a non-selective NET inhibitor (also blocks SERT, sodium channels, muscarinic receptors, and histamine 1 receptors)
- the secondary amine in these is what gives it selectivity for NET

Question 11

Define the class and mechanism of action of atomoxetine.

Answer 11

Tricycline Secondary Amine Antidepressant

Is a non-selective NET inhibitor (also blocks SERT, sodium channels, muscarinic receptors, and histamine 1 receptors)
- the secondary amine in these is what gives it selectivity for NET

Question 12

Define the class and mechanism of action of nisoxetine.

Answer 12

Non-tricyclic Secondary Amine NRI (norepinephrine reuptake inihbitor)

Has a methoxy group that restricts its conformation so that it is selective for NET (norepinephrine reuptake transporter) instead of SERT

Question 13

Define the class and mechanism of action of imipramine.

Answer 13

Tertiary Amine SNRI (serotonin-norepinephrine reuptake inhibitor)

Increases levels of both 5-HT (serotonin) and norepinephrine in the synaptic cleft by blocking both SERT and NET channels

Question 14

Define the class and mechanism of action of amitriptyline.

Answer 14

Tertiary Amine SNRI (serotonin-norepinephrine reuptake inhibitor)

Increases levels of both 5-HT (serotonin) and norepinephrine in the synaptic cleft by blocking both SERT and NET channels.
The propylideneamine moiety makes it sensitive to light.

Question 15

Define the class and mechanism of action of clomipramine.

Answer 15

Tertiary Amine SNRI (serotonin-norepinephrine reuptake inhibitor)

Increases levels of both 5-HT (serotonin) and norepinephrine in the synaptic cleft by blocking both SERT and NET channels.
Most potent because of how preferentially it blocks SERT.

Question 16

Define the class and mechanism of action of trimipramine.

Answer 16

Tertiary Amine SNRI (serotonin-norepinephrine reuptake inhibitor)

Increases levels of both 5-HT (serotonin) and norepinephrine in the synaptic cleft by blocking both SERT and NET channels

Question 17

Define the class and mechanism of action of doxepin.

Answer 17

Tertiary Amine SNRI (serotonin-norepinephrine reuptake inhibitor)

Increases levels of both 5-HT (serotonin) and norepinephrine in the synaptic cleft by blocking both SERT and NET channels

Question 18

Define the class and mechanism of action of venlafaxine.

Answer 18

Noncyclic SNRI (serotonin-norepinephrine reuptake inhibitor)

Works like a normal tricyclic SNRI (blocks SERT and NET), but changing it to be non-cyclic removed unwanted adverse effects of the tricyclic inhibitors.

Venlafaxine is 30 times more potent at blocking SERT than NET, and the metabolite is equally potent.

Question 19

Define the class and mechanism of action of duloxetine.

Answer 19

Noncyclic SNRI (serotonin-norepinephrine reuptake inhibitor)

Works like a normal tricyclic SNRI (blocks SERT and NET), but changing it to be non-cyclic removed unwanted adverse effects of the tricyclic inhibitors.

Duloxetine exhibits dual inhibition with high affinity for both SERT and NET, with a five-fold preferential for SERT.

Question 20

Define the class and mechanism of action of bupropion.

Answer 20

Selective inhibitor of dopamine reuptake at the dopamine presynaptic neuronal membrane and is an NRI (norepinephrine reuptake inhibitor)
(increased by DA and NE)

Also functions as a nicotinic acetylcholine receptor inhibitor underlying various nicotinic effects and cravings associated with smoking cessation, so it can reduce withdrawal symptoms.

Question 21

Define the class and mechanism of action of tranylcypromine and moclobemide.

Answer 21

Monoamine oxidase inhibitors.

Mostly used in atypical depression and bulimia (off-label).

Question 22

Define the class and mechanism of action of lithium.

Answer 22

Mood stabilizer.

Blocks signal transduction pathways. An important one involves inositol triphosphate (IP3). Normally it would be involved in neuronal signaling associated with neural activation, so blocking this reduces the amplitude of mood changes.

Lithium is specific to the CNS because inositol can’t cross the BBB and replenish the levels that have been depleted by lithium.

Question 23

Define the class and mechanism of action of methotrexate.

Answer 23

Immunosuppressant.

Prevents proliferation of immune cells.

Question 24

Define the class and mechanism of action of cyclophosphamide.

Answer 24

Immunosuppressant.

Prevents proliferation of immune cells.

Used in treatment of secondary progressive form of MS.

Question 25

Define the class and mechanism of action of propranolol.

Answer 25

Non-selective beta blocker

Question 26

Define the class and mechanism of action of practolol.

Answer 26

B1 selective beta blocker (first cardio-selective beta blocker)

Question 27

Define the class and mechanism of action of esmolol.

Answer 27

Short-acting beta blocker indicated for use in intraoperative or postoperative tachycardia or hypertension

Question 28

Define the class and mechanism of action of pindolol

Answer 28

Beta blocker has an indole ring that makes it unique

Question 29

Define the class and mechanism of action of timolol.

Answer 29

Beta blocker has a polar heterocyclic ring (thiadiazol-morpholino group) that reduces the log-P value

Question 30

Define the class and mechanism of action of lisinopril.

Answer 30

ACE Inhibitor Antihypertension agent; developed based on how another metalloproteinase enzyme is inhibited.

Question 31

Define the class and mechanism of action of enalapril.

Answer 31

ACE Inhibitor is a prodrug of enalaprilat

Question 32

Define the class and mechanism of action of aliskiren.

Answer 32

Renin inhibitor is a transition state analogue that mimics the tetrahedral geometry of the reaction intermediate

Question 33

Define the class and mechanism of action of lovastatin, pravastatin, and simvastatin.

Answer 33

They are Type 1 Statins Work as an HMG-CoA reductase inhibitor to prevent the formation of cholesterol. Statins are technically transition state analogues because they mimic the transition state of the first reduction step (there are two reductions, both of which involve NADPH in the normal reaction). These three all contain asymmetric centers and are harder to synthesize. Lovastatin and Simvastatin are prodrugs.

Question 34

Define the class and mechanism of action of fluvastatin, atorvastatin, rosuvastatin, and cerivastatin.

Answer 34

Type 2 Statins (HMG-CoA reductase inhibitor) are all synthetic agents that contain a larger hydrophobic moiety than type 1 statins and they don't have asymmetric centers so they're easier to synthesize. Rosuvastatin is very potent because of its sulfonamide group.

Question 35

Define the class and mechanism of action of levodopa (+carbidopa)

Answer 35

Dopamine replacement therapy. L-dopa precursor (levodopa) with a decarboxylase inhibitor (carbidopa) to prevent the L-dopa from being decarboxylated to the active form outside of the CNS.

Question 36

Define the class and mechanism of action of pramipexole and ropinirole.

Answer 36

D2 agonists (Dopamine 2 receptor) Limits the fluctuations in response to L-dopa and prolongs dopaminergic action

Question 37

Define the class and mechanism of action of flupirtine.

Answer 37

Non-opioid non-NSAID analgesic It blocks the chain that is induced by bradykinin - binds to potassium channels, preventing them from opening, and thus blocking the production of the pain response Used in headaches, musculoskeletal pain, neurogenic pain, cancer pain, fibromyalgia, and post-operative pain Advantages: no side effects of NSAIDs and opioids Interacts with warfarin and can increase toxicity

Question 38

Define the class and mechanism of action of amitiza.

Answer 38

Chloride channel activator Indicated in the treatment of chronic idiopathic constipation in adults OR the treatment of IBS-C MOA: activates chloride channels to enhance chloride-rich intestinal fluid secretion. - this increases the motility of the intestine, facilitating the passage of stool and alleviating symptoms associated with chronic idiopathic constipation

Question 39

Define the class and mechanism of action of Linzess (linaclotide).

Answer 39

Guanylate Cyclase-C agonist (GC-C) indicated for treatment of idiopathic constipation OR IBS-C activation of GC-C results in an increase in both intracellular and extracellular cGMP, stimulating secretion of chloride and bicarbonate into the intestinal lumen - results in increased intestinal fluid and accelerated transit

Question 40

Define the class and mechanism of action of Plecanatide (Trulance).

Answer 40

Guanylate Cyclase-C (GC-C) agonist indicated for treatment of chronic idiopathic constipation. activation of GC-C results in an increase in both intracellular and extracellular cGMP, stimulating secretion of chloride and bicarbonate into the intestinal lumen - results in increased intestinal fluid and accelerated transit

Question 41

# Define the class and mechanism of action of docusate (colase). other names include ex-lax and senokot S

Answer 41

Laxative of the Stool Softener Type Indicated for use in constipation Is an anionic surfactant - lowers the surface tension at the oil-water interface of the feces, allowing water and lipids to penetrate the stool - this helps hydrate and soften the fecal material, facilitating natural defecation

Question 42

Define the class and mechanism of action of ondansetron (zofran).

Answer 42

5-HT3 Antagonist Indicated for prevention of nausea and/or vomiting. MOA not fully characterized, but serotonin receptors (of the 5-HT3 type) are present both peripherally on the vagal nerve terminals and centrally in the chemoreceptor trigger zone of the area postrema