Pharmacology

Question 1

What are the sympathetic effects on the heart?

Answer 1

Sympathetic Effects increase cardiac output. Positive chronotropic effect (increased heart rate), positive inotropic effect (increased force of contraction) and positive dromotropic effect (increased speed of conduction of excitation)

Question 2

What are the parasympathetic effect on the heart?

Answer 2

Parasympathetic effects decrease heart rate and cardiac output (force of contraction)

Question 3

What are the overall effects of autonomic drugs on blood pressure (SNS and PSNS)?

Answer 3

Direct effects on the heart: Beta-1 stimulation leads to an increased HR and increased force. Muscarinic stimulation leads to a decreased heart rate and force.

Vascular effects:
Muscarinic stimulation results in dilation which decreases BP (NOTE: no PSNS innervation this is ONLY for exogenous muscarinic drugs). Alpha stimulation results in vascular constriction while beta-2 stimulation results in dilation.

Redistribution of blood:
With increased sympathetic activity, blood is shunted away from organs and towards heart and voluntary muscles. This is due to beta-2 vasodilation predominance over alpha-1 constriction at these sites.

Reflex Phenomena:
Decrease in blood pressure causes reflex tachycardia.

Question 4

What are the effects of overstimulation of Muscarinic receptors?

Answer 4

DUMBELS:
Defecation
Urination
Miosis
Bronchoconstriction
Emesis
Lacrimation
Salivation

Question 5

What are the cardiovascular effects of opioid use?

Answer 5

Decreased myocardial oxygen demand

Vasodilation and orthostatic hypotension

Question 6

What are the GI effects of opioid use?

Answer 6

Decreased gastric motility and constipation (increased muscle tone leads to diminished propulsive peristalsis in colon)
Nausea and vomiting (direct stimulation of chemoreceptor trigger zone)

Question 7

What are the Genitourinary effects of opioid use?

Answer 7

Increased bladder sphincter tone

Increased urine retention

Question 8

What are the general mechanisms of action of antimicrobials?

Answer 8

Cell wall synthesis
Cell membrane
Folic acid metabolism
DNA replication
RNA synthesis
Protein synthesis

Question 9

What processes contribute to antimicrobial resistance?

Answer 9

Altered target proteins:
Beta-lactams, Vancomycin, Aminoglycoside, Macrolide, Tetracycline, Fluoroquinolone

Decreased permeability
Beta-lactams, Tetracycline, Fluoroquinolone

Increased Efflux
Macrolides, Tetracycline, Fluoroquinolone

Enzymatic inactivation:
beta-lactam, aminoglycoside, macrolide, tetracycline

Question 10

Which antibiotics are bactericidal agents?

Answer 10

beta-lactam, isoniazid, aminoglycoside, polymyxin, fluoroquinolone, pyrazinamide

Question 11

Which antibiotics are bacteriostatic agents?

Answer 11

Tetracycline, macrolide, sulphanomide

Question 12

What are the antibiotics that act as cell wall synthesis inhibitors?

Answer 12

Beta-lactams:
Amoxicillin, Dicloxacillin, Penicillin, Ampicillin

Cephalosporins
Vancomycin

Question 13

What are the causes of resistance to cell wall synthesis inhibitors?

Answer 13

Inactivation by beta-lactamases.
Alteration in target penicillin binding proteins
Permeability barrier

Question 14

What are the antibiotics that act against cell membrane?

Answer 14

Daptomycin and Polymyxin

Question 15

What are the antibiotics that act as protein synthesis inhibitors?

Answer 15

Aminoglycosides (Gentamicin and Streptomycin) - bind to 30S

Tetracycline (Doxycycline) - bind to 30S

Macrolide (Clarithromycin and Erythromycin) - bind to 50S

Question 16

What are the antibiotics that act against metabolites?

Answer 16

Sulphanomides

Primary use in UTIs

Question 17

What are the antibiotics that act against DNA replication?

Answer 17

Fluoroquinolone (inhibit DNA gyrase)