CVS drugs - Diuretics and anti-fat Flashcards
When is mannitol used?
Raised ICP
Give a CI for mannitol
Congestive heart failure
Pulmonary oedema
What is the mechanism of aciton of mannitol?
Freely filtered at the glomerulus, but only partially, if at all, reabsorbed
Passive water reabsorption is reduced by the presence of this non-reabsorbable solute within the tubule lumen
What are two ADRs of mannitol?
Chills and fever
When would you use thiazide diuretic?
Hypertension
Oedema
Give mechanism of action of thiazide diuretics
Inhibit NaCl symporter in luminal membrane, more Na+ in tubule
Give four ADRs of thiazide diuretics
Hypokalaemia Hyperuriciaemia Impaired glucose tolerance Hyponatraemia Hyper calcaemia Metabolic alkalosis
Give four thiazide DDIs
Steroids - Increase risk of hypokalaemia
Beta blockers - Hyperglycaemia
Digoxin - Hypokalaemia increases digoxin binding and toxicity
Carbamezapine - Increased risk of hyponatraemia
When would you use loop diuretics?
Acute pulmonary oedema
Oliguria
Resistant heart failure
Hypertension
What is the mechanism of action of loop diuretics?
Inhibit NKCC2 channel at thick ascending limb
Give some ADRs of loop diuretics
Hypokalaemia, Hyponatraemia, hyperuricaemia (can preciptitate gout), hypotension, hypovolaemia, metabolic alkalosis
What can furosemide cause specifically?
Ototoxicity
How do loop diuretics interact with digoxin?
May cause hypokalaemia, increasing digoxin binding
How do aminoglycosides mess with digoxin?
Interact with loop diuretics and increases risk of ototoxicity and potential hearing loss
Give two potassium sparing diuretics
Amiloride
Spironolactone
When are potassium sparing diuretics used generally?
In conjunction with other diuretics for heart failure and hypertension
What can spironolactone be used for specifically?
Hyperaldosteronism
What does amiloride do?
Blocks Na+ reabsorption
What are some ADRs of spironolactone?
Hyperkalaemia
Hyponatraemia
Spironolactone - gynaecomastia, mestural disorders
How is digoxin a diuretic?
Inhibits tubular Na/K ATPase?
How does Lithium work as a diuretic
ADH antagonist
How do you treat hyperkalaemia?
IV calcium gluconate
How do statins work?
HMG-CoA Reductase inhibitor. Prevents cholesterol synthesis in the liver. Lower liver cholesterol concentration stimulates the production of LDL receptors, increasing the rate of LDL removal from plasma.
What are three main ADRs of statins?
Myopathy
Arthralgia
Headaches
What drugs effect statins significantly?
Cyp450 inducers/inhibitors
How much do statins decrease things?
o LDL reduction of between 5-35%,
o HDL raised by ~5%
o Triglycerides reduction of 10-35%
Give four lipid lowering drugs
Fibrates
Statins
Cholesterol absorption inhibitors
Bile Acid Sequesterant
What is the mechanism of fibrates?
PPAR-a agonist
What is PPAR?
Major regulator of lipid metabolism in the liver
Activation promotes uptake, catabolization and utilization of lipids
What do fibrates do?
LDL lowering
HDL increase in 15-25% in hypertriglyceridaemia
Decreases Triglycerides 25-50%
Give some adverse drug reactions to fibrates
Gastrointestinal disturbances
Impotence
Dermatitis
Headache
What happens if you take fibrates with statins?
Myalgia and myopathy
What do cholesterol absorption inhibitors act on?
Intestinal cholesterol uptake - NPC1L1 in brush border.
What does a single dose of cholesterol absorption inhibitor do?
Reduces LDL by 15-20%
Give two ADRs of cholesterol inhibitors
Diarrhoea, pain
Headache
What do bile acid sequesterants do?
o Bind to bile acids in the intestine. This prevents their reabsorption and subsequent conversion of hepatic cholesterol into bile acids. Lower levels of hepatic cholesterol leads to increased LDL receptor expression and lowered plasma cholesterol concentration.
Why don’t bile acid sequestrants cause systemic ADRs?
Not well absorbed - Do cause
Nausea, vomiting, constipation, abdominal pain, flatulence, heart burn
