Pharmacology Flashcards
Gq
Contraction of vascular smooth muscle
a1
Gi
Inhibition of noradrenaline release
a2
Gs
Positive inotropic and chronotropic effect
B1
Gs
Relaxation of bronchial smooth muscle
B2
Gq
Increased gastric acid secretion
M1
Gi
Decreased HR
M2
Gq
Increased saliva
Visceral smooth muscle contraction
M3
Gs stimulates
Adenylyl cyclase
Gq
Stimulation of phospholipase C
Gi
Inhibition of adenylyl cyclase
Drug elimination rate independent of dose
Zero order kinetics
Drug elimination proportional to dose
First order kinetics
What is the steady state
Rate admin = rate elimination
Phase I metabolism
Oxidation, hydrolysis and reduction
Phase II metabolism
conjugation to make more hydrophilic
Examples of biguanides
Metformin
Action of biguanide
Decreases hepatic gluconeogenesis via AMP protein kinases
Increases peripheral uptake
Reduces carb absorption
Increases fatty acid oxidation
Indications for metformin
1st line T2DM
Protective against risks
WEIGHT LOSS
No hypoglycemia risk
Side effects of metformin
GI upset
Lactic acidosis
Sulfonylureas examples
Tolbutamide
Gliclazide
Sulfonurea action
Displaces Mg-ADP on SUR1 from Katp channel
B cell depolarises
Stimulates insulin release
Sulfonylurea indications
Add on T2DM
MODY ( HNF-1a)
Sulfonylurea side effects
Weight gain
HYPOglycemia
LFT derangement
Thiazolidione example
Pioglitazone
Thiazolinediones action
PPARy activator to:
Increase insulin signalling (more glucose uptake)
Increased uptake and metabolism of FAs (reduce resistance)
Thiazolinedione usage
Add on in T2DM (HbA1c reduced by 0.6-1.5%)
Contraindications of thiazolinediones
3-5kg weight gain
Fracture risk
Hepatotoxic
fluid retention
SGLT-2 inhibitors
Dapagliflozin
Canagliflozin
Empagliflozin
SGLT-2 inhibitor mechanism
blocks SGLT-2 to prevent glucose reabsoprtion in PCT
Uses
Add on T2DM
sglt-2 side effects
UTIs
Ketoacidosis
DPP4 inhibitors
‘gliptins’
DPP4 inhibitor action
inhibits DPP4 enzyme so GLP-1 and GLP can work longer
Increases insulin and decreases glucagon
DPP4 uses
alone/ add on to T2DM
DPP4 side effets
Nausea
GLP-1 receptor agonists
extenatide
Liraglutide
GLP-1 action
Mimics GLP-1 to incrase insulin secretion
resistant to DPP4
Uses of GLP-1
Good for meal relateed hyperglycemia
a Glucosidase inhibitors
acarbose
voglibose
migitiol
a Glucosidase action
inhibits a glucosidase to decrease starch breakdown
Reduced glucose absorbed
Acetazolimide class
CA inhibitor
CA inhibitor action
inhibits CA to increase HCO3 so more Na+ excreted
CA inhibitor usage
glaucoma (reduced intraocular pressure)
Furosemide
Bumetinide
Loop diurectics
Loop diuretics action
Inhibits triple transport so less Na, K and Cl pumped out
Less water leaves descending limb
More K, Mg, Ca loss
Loop diuretics usage
Salt and water overload
Hypertension
Lopp diuretics side efects
Dont use when BP low Low Na, K, metabolic acidosis Gout Hearing loss
Thiazide diuretics
Bendroflumethiazide also: Chlortalidone Indapamide Metolozone
Action of thiazides
Na-Cl in DCT
More Na (and K) pissed out
more water pissed out
Mg loss
Thiazide action
mild heart failure
Hypertension
renal stones
Diabetes insipidus
Side effects of thiazides
Decreased Na, K, Mg Gout Metabolic acidosis ED Hypotension
Potassium sparing diuretics
Amiloride and triamterene
Spironolactone and eplerenone
Use of K sparing ABs
Heart failure
Hyperalosteronism
Hypertension
Action of K sparing ABs
Amiloride and triametrene:
Block apical Na channels to reduce uptake (but no K loss as its the collecting ducts)
Spironolactone
Aldosterone antagonists to prevent salt and water uptake (No Na reabsorption so no K loss)
When to avoid K sparing drugs
Hypokalaemia
Severe renal impairment
Addisons
What is mannitol
Osmotic diuretic
Increases osmolarity in PCT to reduce movement of water
Maintains renal flow and reduces ICP
Vaptans
Conivaptan
Tolvaptain
Vaptan action
Antagonists of V receptors on aquaporin 2 channels to prevent ADH action
Water excreted without Na loss
When are vaptans used?
SIADH
Hypervolaemia
Hyponatraemia
Uricosuric agents
probenicid
Block reabsorption of urate in PCT
used for gout
Antimuscarnics
oxybutynin
tolteridione
Solfenacin
Prevent overactive bladder contracting
Side effects of antimuscarinics
Heat stroke
Dry mouth
Urinary retention
B3 andrenergics
Mirabegnon
Relaxes detrusor
used in urge incontinence
A blocker
Tamulosin
A1 receptor antagonist to prostate to relax muscles
Used in kidney stones and urinary retention
A blocker side efects
Allergy
Hypotension
Duloxetine
Stress incontinence
NSAID examples
Aspirin
ibuprofen
naproxen
diclofenac
NSAID mechanism
Block COX to prevent PG release so reduced pain sensation and inflammation
Side effects of NSAIDs
GI problems
Renal impairment
Wheeze
Rash
DMARD examples
MTX SFZ Azathioprine lefluonimide HCQ
DMARD use
Reduce rate of joint damage
Side effects DMARDS
Liver damage (monitor LFTs)
ulcers
TERATOGENIC
Biologics examples
-imabs
Biologics action
Inhibit immune system (generally TNF)
used in autoimmune arthritis coniiditons
Side effect of biologics
TB reactivation
Urate lowering drugs
Allopurinol
Febuxostat
Action of urate lowerig drugs
xanthine oxidase inhibitors so no urate synthesis
Use of urate lowering drugs
Chronic gout
Side effects of urate lowering drugs
Azathioprine interactons
Acamprosate mechanism and use?
Stabilises chemical signalling alcohol dependence (reduces pleasure)
Naltrexone mechanism and use
Opioid receptor antagonist
Reduces amount and frequency of drinking
DOnt give in liver failure
Dilsulfiram mechanism and use
Inhibits acetaldehyde dehydrogenase enzyme so hangover symptoms (nausea, vomiting tc) when drinnking
2nd line alcohol dependence
Pabrinex and thiamine mechanism and use
Thiamine supplements
Wernicke-korsakoff syndrome (give with glucose infusion)
Diazepam mechanism and use
GABA A receptor modulator
Makes neurone less likely to fire
Calming effects
Side effects of diazepam
confusion
sedation
amnesia
falls
