HLB Core Drugs Flashcards
Key Drugs
<p>What are cardiac glycosides?</p>
<p>- organic compounds (carbon backbone)</p>
<p>- able to increaseinotropic contraction force</p>
<p>What are cardiac glycosides used for?</p>
<p>- atrial fibrillation and flutter</p>
<p>- heart failure</p>
<p>What is the most common drug used as a cardiac glycoside?</p>
<p>- digoxin</p>
<p>What is the mechanism of action of digoxin, a cardiac glycoside?</p>
<p>- inhibits the enzyme ATPase</p>
<p>- stop N+ / K+ ATPase pump</p>
<p>- Na+ ⬆️inside the cell</p>
<p>- Na+ leaves via Na+ / Ca2+ exchanger and Ca2+ ⬆️ inside the cell</p>
<p>Why is N+ / K+ ATPase so important in cells?</p>
<p>- maintains resting membrane potential</p>
<p>- maintain electrochemical charge</p>
<p>In normal physiology in cardiomyocytes what does the N+ / K+ ATPase use to move cations against concentrations gradients and what moves into the cell and what moves outside the cell?</p>
<p>- ATP used</p>
<p>- Na+ moves out of cell (3)</p>
<p>- K+ moves into cell (2)</p>
<p>What is ATPase?</p>
<p>- enzyme inside cells</p>
<p>- hydrolyses ATP to ADP</p>
<p>If Na+ / K+ ATPase is working normally what happens to the cell?</p>
<p>- 3 Na+ leave and 2 K+ enter the cell</p>
<p>How does inhibiting N+ / K+ ATPase increase inotropic force?</p>
<p>- Na+ remains in cell</p>
<p>- Na+ can leave through Na+ / Ca2+ exchanger</p>
<p>- Na+ leaves and Ca2+ enters</p>
<p>In addition to inhibiting N+ / K+ ATPase and increasing intracellular Ca2+, what other mechanism is digoxin able to work through?</p>
<p>- stimulates the vagus nerve (parasympathetic)</p>
<p>- reduced HR through SA and AV node</p>
<p>Why can digoxin, a cardiac glycoside be useful in treating chronic heart failure (CHF) patients?</p>
<p>- CHF means heart is weakened</p>
<p>- digoxin ⬆️ inotropic force</p>
<p>What is the renin angiotensin aldosterone system, commonly referred to as RAAS?</p>
<p>- hormone system that regulates blood pressure</p>
<p>Why is the renin angiotensin aldosterone system (RAAS) written in this order?</p>
<p>- this is the order blood pressure is controlled</p>
<p>What is renin (also known as angiotensinogenase) as part of RAAS?</p>
<p>- proteolytic enzyme</p>
<p>- cleaves angiotensinogen released from the liver</p>
<p>- creates angiotensin 1</p>
<p>What is angiotensinogen as part of the RAAS?</p>
<p>- alpha 2 globulin</p>
<p>- released by the liver, a precursor for angiotensin 1</p>
<p>When do the kidneys secrete renin in the RAAS system?</p>
<p>- when blood flow or blood volume to the kidneys is reduced</p>
<p>- specifically the juxtaglomerular cells in the kidneys</p>
<p>- blood vessels vasoconstrict in attempt to increase blood flow</p>
<p>What is angiotensin I as part of the RAAS?</p>
<p>- a weak vasoconstrictor</p>
<p>Is angiotensin II, part of the RAAS the strongest vasodilator in the body?</p>
<p>- no</p>
<p>- 2nd strongest vasoconstrictor in the body</p>
<p>What is angiotensin converting enzyme?</p>
<p>- enzyme able to cleave amino acid off angiotensin I</p>
<p>- creates angiotensin II</p>
<p>What type of receptor is present on smooth muscles that angiotensin II is able to act upon and cause vasoconstriction?</p>
<p>- GPCR - specifically Gaq</p>
<p>- ⬆️ Ca2+ = contraction</p>
<p>To help identify which drugs are ACE inhibitors, what do the drugs names generally end in?</p>
<p>- pril</p>
<p>- like ramipril</p>
<p>What is bradykinin?</p>
<p>- peptide</p>
<p>- promotes inflammation and vasodilation</p>
<p>What does bradykinin trigger the release of from endothelium cells?</p>
<p>- prostacyclin</p>
<p>- nitric oxide</p>
<p>- endothelins (strongest dilator in the body)</p>
<p>What is one of the most commonly prescribed ACE inhibitors?</p>
<p>- ramipril</p>
<p>Although ramipril is an effective hypertensive agent, there are some side effects that patients may experience. What are those?</p>
<p>- dry cough (due to bradykinin accumulation)</p>
<p>- renal impairment</p>
<p>- hyperkalaemia (can be given with diuretic)</p>
<p>ACE inhibitors such as ramipril are generally used to treat hypertension, but why can they be useful when treating heart failure?</p>
<p>- ⬇️ systemic vascular resistance (SVR)</p>
<p>- ⬇️ SVR = ⬇️ afterload (resistance against heart beat)</p>
<p>- heart failure patients have a weak heart</p>
<p>- ⬇️ afterload reduces workload on the heart</p>
<p>What is the normal physiological effect of angiotensin II on aldosterone levels?</p>
<p>- stimulates the adrenal cortex</p>
<p>- aldosterone is released from zona glomerulosa cells</p>
<p>- increases blood volume and BP</p>
<p>Angiotensin II is able to stimulate zona glomerulosa cells of the adrenal cortex releasing aldosterone, which can then go on to increase blood volume and BP. How does aldosterone increase blood volume and BP?</p>
<p>- signals to distal tubules in renal tubules</p>
<p>- retain Na+ and and H2O</p>
<p>- ⬆️ Na+ and H2O = ⬆️ blood volume</p>
<p>- ⬆️ blood volume = ⬆️ BP</p>
<p>What is the normal physiological effect of angiotensin II on the pituitary gland?</p>
<p>- baroreceptors recognise need to ⬆️ BP</p>
<p>- hypothalamus signals pituitary gland</p>
<p>- pituitary gland secretes anti-diuretic hormone</p>
<p>The pituitary gland secretes anti-diuretic hormone (opposite effect of diuretci drugs to treat hypertension) in response to angiotensin II. How does the release of anti-diuretic hormone effect BP?</p>
<p>- stimulates kidneys to retain H2O</p>
<p>- ⬆️ H2O = ⬆️ blood volume</p>
<p>- ⬆️ blood volume = ⬆️ BP</p>
<p>- partial arteriole vasoconstrction</p>
<p>Ramipril is an ACE inhibitor, which means it can inhibit the conversion of angiotensin I to angiotensin II. If ACE is inhibited by Ramipril, what are the 3 main effects this can have on the RAAS system?</p>
<p>- ⬇️ smooth muscle vasoconstriction</p>
<p>- ⬇️ H2O retention due to anti-diuretic hormone</p>
<p>- ⬇️ Na+ and H2O retention due to aldosterone</p>
<p>When treating hypertension, we need to remember how to calculate BP, which is cardiac output (CO) x systemic vascular resistance (SVR). Therefore what are the main effects on CO and/or SVR that ACE inhibitors have?</p>
<p>- ⬇️ systemic vascular resistance</p>
<p>What are muscarinic antagonist drugs?</p>
<p>- those that inhibit muscarinic receptors</p>
<p>- M1 = Gaq</p>
<p>- M2 = Gai</p>
<p>- M3 = Gaq</p>
<p>What do muscarinic antagonist drugs do to the parasympathetic activity?</p>
<p>- reduce the activity</p>
<p>Why are muscarinic antagonist drugs commonly called anti-cholinergic?</p>
<p>- muscarinic receptors are a form of cholinergic receptor</p>
<p>- inhibit muscarinic means anti-cholinergic</p>
<p>What is one of the most commonly prescribed muscarinic antagonist drugs?</p>
<p>- atropine</p>
<p>What is atropine used for in the heart?</p>
<p>- treat people with bradycardia</p>
<p>- patients have low HR</p>
<p>- patients may have lower CO</p>
<p>What is the mechanism of action of atropine?</p>
<p>- competitive antagonist</p>
<p>- inhibits acetylcholine and therefore muscarinic receptors</p>
<p>In a normal physiological response what does the muscarinic receptor M2 do to the heart?</p>
<p>- inhibit adenylyl cyclase (AC) as part of Gai</p>
<p>- ⬇️ AC = ⬇️ HR and inotropic contraction</p>
<p>Atropine is a non selective competitive antagonist, meaning it can compete with acetylcholine and inhibit its activity when binding to muscarinic receptors. Although it has a wide range of effects, what does atropine do to the heart in patients with bradycardia?</p>
<p>- does not inhibit adenylyl cyclase (AC) in Gas</p>
<p>- ⬆️ activation of SA node = ⬆️ HR</p>
<p>- ⬆️ inotropic contraction</p>
<p>What are diuretics?</p>
<p>- drugs that ⬆️ urine excretion</p>
<p>- drugs that ⬆️ Na+ and Cl- excretion</p>
<p>What is the most commonly used thiazide diuretic to treat high blood pressure?</p>
<p>- bendroflumethiazide</p>
<p>Where in the kidneys is blood filtered to form the filtrate?</p>
<p>- blood enters glomerulus</p>
<p>- blood is then filtered into the filtrate</p>
<p>Once the filtrate is formed from the glomerulus, what happens to the fluid as it move through the tubules and out of the collecting duct as urine?</p>
<p>- H2O and other molecules are re-absorbed into blood</p>
<p>- what is left is urine</p>
<p>Where are ions mainly re-absorbed in the renal system?</p>
<p>- distal convelutedtubules</p>
<p>- location of most diuretics actions</p>
<p>What passively follows ion re-absorption in the distal tubules of the renal system, which ion specifically does it follow?</p>
<p>- Na+</p>
<p>- due to osmosis (H2O dilutes Na+ in blood)</p>
<p>In normal physiology how are Na+ and Cl- re-absorbed from the filtrate into the blood from the renal system?</p>
<p>- through thiazide sensitive Na+ / Cl- co-transporter into epithelial cells</p>
<p>- Na+ reabosrbed using Na+ / K+ ATPase</p>
<p>- Cl- channels reabsorb Cl-</p>
<p>What is the mechanism of action of bendroflumethiazide on the renal system and thus lower blood pressure?</p>
<p>- inhibits thiazide sensitive Na+ / Cl- co-transporter</p>
<p>- Na+ and Cl- excreated out in urine</p>
<p>- H2O follows Na+</p>
<p>How does increased Na+ in the blood cause an increase in blood pressure?</p>
<p>- Na+ retains H2O</p>
<p>- ⬆️ volume in blood vessels = ⬆️ pressure</p>
<p>What is one of the most commonly used thiazide like drugs to treat hypertension?</p>
<p>- Indapamide</p>
<p>In normal physiological response of smooth muscle vasoconstriction or vasodilation, what happens to the ATP sensitive K+ channels and the Ca2+ voltage gated channels on the smooth muscle cells?</p>
<p>- vasoconstriction = ⬇️ K+ ATPase</p>
<p>- ⬇️ ATPase activity = ⬇️ K+ leaves and ⬆️ Ca2+ enters cell</p>
<p></p>
<p>- vasodilation = ⬆️ K+ ATPase</p>
<p>- K+ channel opens ⬆️ K+ inside cell and hyperpolarisation (⬆️ negative)</p>
<p>- ⬆️ K+ leaves and ⬇️ Ca2+ enters cell</p>
<p>In addition to inhibiting the thiazide sensitive Na+ / Cl- co-transporter, Indapamide also acts at lowering blood pressure through a second mechanism, what is this?</p>
<p>- dilate blood vessels</p>
<p>- ATPase sensitive K+ channels ⬆️ K+ leaving cell (⬆️ negative inside)</p>
<p>- reduces Ca2+ entry into blood vessels</p>
<p>In addition to bendroflumethiazide and Indapamide, what is the 3rd diuretic drug we are expected to know?</p>
<p>- furosemide</p>
<p>What are the 3 thiazide or thiazide like diuretics that are are expected to know? (all end in ide)</p>
<p>1 - bendroflumethiazide</p>
<p>2 - indapamide</p>
<p>3 - furosemide</p>
<p>What are some common side effects of diuretics?</p>
<p>- Hyponatraemia (Na+) - Hypokalaemia (K+) - Alkalosis (H +) - Hypercalcaemia (Ca2+) - Hypomagnesaemia (Mg2+) - ⬆️ in urate (gout) - ⬆️ blood glucose - ⬆️ lipids</p>
<p>When treating hypertension, we need to remember how to calculate BP, which is cardiac output (CO) x systemic vascular resistance (SVR). Therefore what are the main effects on CO and/or SVR that thiazide and/or thiazide like diuretics have on CO and/or SVR?</p>
<p>- blood volume</p>
<p>- blood volume, increases preload</p>
<p>- preload increases SV</p>
<p>- SV increases CO</p>
<p>How can thiazide and thiazide like diuretics cause hyponatraemia (⬇️ Na+), Hypokalaemia (⬇️ K+) and hypercalcaemia (⬆️ Ca2+)?</p>
<p>- Na+ and K+ not re-absorbed</p>
<p>- Na+ moves down concentration gradient from blood into epithelial cells</p>
<p>- Na+ / Ca2+ exchanger swaps Na+ anjd Ca2+</p>
<p>- Ca2+ swaps places and leaves epithelail cell into blood</p>
<p>In normal physiology how does Na+ and Cl- get re-absorbed from the distal tubules into the cells?</p>
<p>- through the Na+ / Cl- co-transporter</p>
<p>In normal physiology, once Na+ and Cl- have been re-absorbed from the distal tubules through the Na+ / Cl- co-transporter into the epithelialcells, how is Na+ able to be re-absorbed into the blood?</p>
<p>- through Na+ / K+ ATPase pump</p>
<p>- 3 Na+ out of cell into blood</p>
<p>- 2 K+ into cell and out of blood</p>
<p>- K+ is able to leave eputhelail cell through K+ channel</p>
<p>In addition to moving from the distal tubules through the Na+ / Cl- co-transporter and back into blood through the N+ / K+ ATPase pump, how can some of the Na+ re-enter the same cell epithelail cellit just left?</p>
<p>- through Na+ / Ca2+ exchanger</p>
<p>- Ca2+ in renal cells is ⬇️</p>
<p>- creates Ca2+ and Na+ concentration gradient</p>
<p>- higher Ca2+ in distal tubules epithelial cells compared to blood</p>
<p>- Ca2+ moves from epithelailcells into blood</p>
<p>How can thiazide and thiazide like diuretics cause metabolic acidosis?</p>
<p>- ⬇️ Cl- re-absorbed- Cl- used to balance carbonic anhydrase with HCO3-</p>
<p>What is aldosterone?</p>
<p>- hormone release by adrenal glands</p>
<p>What is the role of aldosterone in the body?</p>
<p>- signals kidneys to retain Na+ and H2O and excrete K+</p>
<p>- ⬆️ Na+ and H2O = ⬆️ blood pressure</p>
<p>What do aldosterone antagonists do to the body?</p>
<p>- ⬇️ Na+ and H2O re-absorption</p>
<p>- ⬇️ blood volume and BP</p>
<p>What is one of the most commonly prescribed drugs that act as aldosterone antagonists that we need to know?</p>
<p>- Spironolactone</p>
<p>What is the structure of the aldosterone antagonists, Spironolactone, similar to?</p>
<p>- estrogen</p>
<p>What is the mechanism of action of Spironolactone?</p>
<p>-inhibits Na+ pump and ⬇️ Na+ reabsorption from lumen</p>
<p>- inhibits Na+ / K+ ATPase at basolateral membrane (blood)</p>
<p>- Na+ is not re-absorbed</p>
<p>As spironolactone resembles oestrogen in structure, what is one of the most common side effects of spironolactone?</p>
<p>- Gynaecomastia (man boobs)</p>
<p>In addition to Gynaecomastia, what are 2 other common side effects of Spironolactone?</p>
<p>- Impaired renal function</p>
<p>- Hyperkalaemia (K+)</p>
<p>What are adrenergic receptors?</p>
<p>- GPCRs - part of sympathetic system</p>
<p>What hormones activate adrenergic receptors?</p>
<p>- catecholamines- adrenaline and noradrenaline (main 2)</p>
<p>What are the 2 main groups of adrenergic receptors?</p>
<p>- alpha (a)- beta (B)</p>
<p>What type of transmembrane receptors are all adrenergic receptors?</p>
<p>- GPCRs</p>
<p>How many alpha adrenergic receptors are there?</p>
<p>- 2- alpha 1 and 2</p>
<p>How many beta adrenergic receptors are there?</p>
<p>- 3- B1, B2 and B3</p>
<p>Which GPCR do alpha receptors use to activate intracellular pathways?</p>
<p>- a1 = Gaq- a2 = Gai</p>
<p>Which GPCR do beta receptors use to activate intracellular pathways?</p>
<p>- all Gas</p>
<p>What is the basic intracellular pathway for Gaq?</p>
<p>- phospholipase C is activated and cleaves PiP</p>
<p>- IP3 and DAG are formed</p>
<p>- IP3 increases Ca2+</p>
<p>- Ca2+ binds with DAG and activates protein kinase C</p>
<p>- protein kinase C can phosphorylate inside cell</p>
<p>What is the basic intracellular pathway for Gas?</p>
<p>- adenlyly cyclase (AC) is activated</p>
<p>- AC converts ATP into cAMP</p>
<p>- cAMP activates protein kinase A</p>
<p>- protein kinase A can phosphorylate inside cell</p>
<p>What is the primary function of a1 adrenoreceptors receptors during fight or flight?</p>
<p>- vasoconstriction (primarily blood vessels)</p>
<p>- bladder sphincter contraction</p>
<p>What is the primary function of a2 adrenoreceptors receptors during fight or flight?</p>
<p>- inhibit release of noradrenaline</p>
<p>- inhibit release of acetycholine</p>
<p>- inhibit release of insulin</p>
<p>What is the primary function of B1 adrenoreceptors receptors during fight or flight?</p>
<p>- ⬆️ Heart rate</p>
<p>- ⬆️ Inotrophic contractility</p>
<p>- ⬆️ Renin release (fluid and salt retention)</p>
<p>What is the primary function of B2 adrenoreceptors receptors during fight or flight?</p>
<p>- Vasodilation (skeletal muscle)</p>
<p>- Bronchodilation</p>
<p>- Gluconeogenesis (⬆️ glucose from liver)</p>
<p>Propranolol was the first ever beta blocker invented. What beta channels does in block?</p>
<p>- all as it is a non selective beta blocker</p>
<p>- inhibits B1 and B2 adrenergic receptors</p>
<p>What can Propranolol be used for in treatment?</p>
<p>- angina, hypertension, arrhythmias</p>
<p>- migraine, tremor</p>
<p>- anxiety</p>
<p>- thyrotoxicosis (excessive thyroid hormone)</p>
<p>What are beta blockers (specifically beta 1) able do to the heart in relation to BP?</p>
<p>- ⬇️ HR</p>
<p>- ⬇️ inotropic force</p>
<p>- ⬇️ afterload (SVR) through reduced renin release</p>
<p>What are 2 common side effects of beta blockers (specifically beta 1) that can occur?</p>
<p>- bradycardia</p>
<p>- fatigue</p>
<p>Why canbeta blockers be dangerous in the lungs when using them to treat patients with heart disease?</p>
<p>- inhibit B2 adrenoreceptors</p>
<p>- bronchoconstriction</p>
<p>- ⬆️breathlessness</p>
<p>- dangerous in asthma/COPD</p>
<p>Beta blockers (specifically beta 1) are useful drugs when treating the heart, but what are some side effects that they can have on arterioles in the circulatory system?</p>
<p>- ⬇️ blood supply to skeletal muscles</p>
<p>- ⬇️ blood supply to skin (cause claudication and cold hands)</p>
<p>- ⬇️ blood supply to penis</p>
<p>What is a useful method for remembering which beta blockers are present in the heart and lungs?</p>
<p>- B1 = heart - we have 1 heart</p>
<p>- B2 = lung - we have 2 lungs</p>
<p>What is the most commonly used B1 adrenergic antagonist, also called a beta blockers?</p>
<p>- Bisoprolol</p>
<p>Although Bisoprolol does reduce the side effects when compared with Propranolol, there can be one dangerous side effect in patients with diabetes. Hypoglycaemia causes release of adrenaline, causing gluconeogeneis in the liver in an attempt to release glucose. What symptoms can patient with diabetes experience when hypoglycaemic due to adrenaline?</p>
<p>- sweating, tremor, irritation and palpitations</p>
<p>- symptoms of adrenaline help patients know they may be hypoglycaemic</p>
<p>Why can it be dangerous for patients who are diabetic to take beta blockers?</p>
<p>- B1 adrenergic antagonist/blockers block symptoms associated with hypoglycaemia</p>
<p>- especially dangerous in non selective beta blockers</p>
<p>When treating hypertension, we need to remember how to calculate BP, which is cardiac output (CO) x systemic vascular resistance (SVR). Therefore what are the main effects on CO and/or SVR that adrenergic antagonists/blockers affect?</p>
<p>- CO</p>
<p>- ⬇️ inotrophy</p>
<p>- ⬇️ HR</p>
<p>- ⬇️ renin release</p>
<p>What do angiotensin II receptor antagonists do?</p>
<p>- inhibit the binding of angiotensin II</p>
<p>What type of membrane receptors are present on smooth muscle to receive stimulus from angiotensin II and vasoconstrict?</p>
<p>- GCPR, specifically Gaq</p>
<p>- phospholipase C cleaves PiP2</p>
<p>- forms IP3 and DAG</p>
<p>- IP3 stimulates ⬆️ Ca2+ release</p>
<p>- Ca2+ and DAG activate protein kinase C</p>
<p>Which GPCR are all angiotensin II receptors?</p>
<p>- Gaq</p>
<p>What is the most commonly prescribed angiotensin II receptor antagonists (AR-II blockers), and generally the first and most commonly prescribed medication for hypertension?</p>
<p>- Losartan</p>
<p>When treating hypertension, we need to remember how to calculate BP, which is cardiac output (CO) x systemic vascular resistance (SVR). Therefore what are the main effects on CO and/or SVR that angiotensin II receptor inhibitors have?</p>
<p>- ⬇️ systemic vascular resistance</p>
<p>How many alpha receptors are there?</p>
<p>- 2</p>
<p>- alpha 1</p>
<p>- alpha 2</p>
<p>Do adrenergic receptors act on the sympathetic or parasympathetic system?</p>
<p>- sympathetic</p>
<p>Which catecholamines act on the adrenergic receptors?</p>
<p>- adrenaline</p>
<p>- noradrenaline</p>
<p>What are the main functions of the adrenergic alpha 1 receptors?</p>
<p>- smooth muscle vasoconstriction</p>
<p>- sweating</p>
<p>- bladder sphincter closure</p>
<p>What are the main functions of the adrenergic alpha 2 receptors?</p>
<p>- inhibit release of noradrenaline</p>
<p>- inhibit release of ACh</p>
<p>- inhibit release of Insulin</p>
<p>Adrenergic receptors are all GPCR, specifically which GPCR are present on alpha 1 and 2 receptors?</p>
<p>- alpha 1 = Gaq</p>
<p>- alpha 2 = Gai</p>
<p>What is the basic intracellular pathway once Gaq has been activated?</p>
<p>- GCPR, specifically Gaq</p>
<p>- phospholipase C cleaves PiP2</p>
<p>- forms IP3 and DAG</p>
<p>- IP3 stimulates ⬆️ Ca2+ release</p>
<p>- Ca2+ and DAG activate protein kinase C</p>
<p>What is the basic intracellular pathway once Gai has been activated?</p>
<p>- inhibits adenylyl cyclase released by Gas</p>
<p>When treating hypertension, we need to remember how to calculate BP, which is cardiac output (CO) x systemic vascular resistance (SVR). Therefore what are the main effects on CO and/or SVR that alpha inhibitors have?</p>
<p>- inhibit vasoconstriction of blood vessels</p>
<p>- ⬇️ systemic vascular resistance</p>
<p>What is a common drug prescribed as an alpha 1 inhibitor that we need to know about?</p>
<p>- doxazosin</p>
<p>What is the mechanism of action of the alpha 1 inhibitor doxazosin?</p>
<p>- binds to alpha 1 receptors</p>
<p>- inhibits Gaq</p>
<p>Is doxazosin a competitive or non-competitive inhibitor?</p>
<p>- competitive</p>
<p>Is doxazosin a selective or non-selective alpha inhibitor?</p>
<p>- selective alpha 1 inhibitor</p>
<p>Doxazosin is a selective competitive alpha inhibitors. What is the main effect of this drug?</p>
<p>- vasodilation of smooth muscle</p>
<p>- ⬇️ systemic vascular resistance and BP</p>
<p>What are the 2 most common side effects of the alpha 1 antagonist doxazosin?</p>
<p>- postural hypotension</p>
<p>- tachycardia (reflex tachycardia)</p>
<p>Doxazosin can cause postural hypotension in older patients, why is this?</p>
<p>- Doxazosin vasodilates blood vessels</p>
<p>- upon standing blood vessels do not contract quickly</p>
<p>- fall in blood pressure occurs and patients faint</p>
<p>Doxazosin can cause postural hypotension in older patients, which in turn causes tachycardia reflex, commonly known as palpitations. What is tachycardia reflex?</p>
<p>- ⬇️ in BP causes ⬆️ in adrenalin</p>
<p>- ⬆️ in HR follows to compensate and maintain CO</p>
<p>What are calcium channel blockers?</p>
<p>- drugs that block Ca2+ entering a muscle cell</p>
<p>What are the 2 main groups of calcium channel blockers?</p>
<p>1 - dihydopyridines (mainly blood vessel dilation)</p>
<p>2 - non-dihydopyridines (mainly effects on heart)</p>
<p>What is the most commonly prescribed calcium channel blocker in the UK, that is a dihydopyridine?</p>
<p>- Amlodipine</p>
<p>What are 2 other drugs that are classed as non-dihydopyridines that can be prescribed as calcium channel blockers?</p>
<p>- Diltiazem- Verapamil</p>