year 3 drugs of the week Flashcards
what are ramipril, enalapril and lisinopril examples of?
Angiotensin-converting enzyme (ACE) inhibitors
ACE inhibitors MoA
block ACE — prevent it from converting angiotensin I to its active form angiotensin II; decrease aldosterone secretion
what are 3 indications for ACE inhibitors?
- hypertension
- heart failure
- secondary prevention CVD
ACE inhibitor dosing
dosing individual to each medication — start low and increase to maximum dose tolerated by the patient
what are 4 contraindications to ACE inhibitors?
- severe aortic stenosis
- severe hyperkalaemia
- symptomatic hypotension
- history of angioedema
ACE inhibitors cautions
- moderate renal impairment
- mild hyperkalaemia
- asymptomatic hypotension or at risk of hypotension
- ethnicity — higher rate of angioedema in black patients than in non black patients
- may be less effective in lowering BP in black peoples than in non black patients
cautions from passmed: avoid in pregnancy and breastfeeding, caution in renovascular disease (may result in renal impairment), aortic stenosis (may result in hypotension), hereditary of idiopathic angioedema
what is generally recommended before initiating ACE inhibitor treatment?
correct dehydration, hypovolaemia or salt depletion
what are side effects of ACE inhibitors?
common (not exhaustive):
dry cough, dizziness, dry mouth, electrolyte imbalance (hyperkalaemia), GI discomfort (diarrhoea/constipation), headache, hypotension, nausea
from passmed: cough, angioedema, hyperkalaemia, first dose hypertension (more common in patients taking diuretics)
what should be monitored during ACE inhibitor treatment and checked before starting/increasing dose?
renal function and electrolytes
ACE inhibitors in pregnancy?
recommended during 1st trimester and contraindicated during the 2nd and 3rd trimesters
what percentage of people on ACEi get a dry cough?
10% — if it occurs the only way to stop it is to discontinue the medication and start another class of drugs
what are bisoprolol, atenolol, and betaxolol?
beta blockers
how do beta blockers work?
block the B1 receptors of the autonomic nervous system — slows the heart rate and reduces contractility of the heart
cardioselective beta blockers are 20x more potent at blocking what?
beta 1 receptors than b2 (located in the bronchial smooth muscle of the airways, which has the potential to cause bronchoconstriction)
what are 4 indications for beta blockers?
- hypertension
- heart failure
- secondary prevention CVD
- atrial fibrillation
beta blocker dosing
dosing individual to each medication — start low and increase to max dose tolerated by the patient
what are some contraindications to beta blockers?
- asthma (risk of bronchospasm)
- hypotension
- marked bradycardia
- severe peripheral arterial disease
- uncontrolled heart failure
beta blocker cautions
- diabetes (symptoms of hypoglycaemia may be masked)
- history of obstructive airways disease (introduce cautiously)
- portal hypertension (risk of deterioration in liver function)
- symptoms of thyrotoxicosis may be masked
what are some side effects of beta blockers?
common (not exhaustive):
- coldness of the peripheries
- headaches
- syncope
- erectile dysfunction
- dizziness
- hypotension
- sleep disturbances
beta blocker monitoring?
monitor lung function in patients with a history of obstructive airway disease
what can sudden cessation of a beta blocker cause?
a rebound worsening of myocardial ischaemia — therefore gradual reduction of dose is preferable when beta blockers are to be stopped
what are losartan and valsartan examples of?
angiotensin receptor blockers (ARBs)
ARB MoA
- reduce the action of angiotensin II to prevent blood vessel constriction
- angiotensin II also stimulates salt and water retention in the body, so reducing this action also reduces BP
what are 3 indications for ARBs?
- hypertension
- congestive heart failure
- diabetic nephropathy