Beta Adrenoceptor Blockers Flashcards
Sympathetic response in eyes?
Pupil dilation
Sympathetic response in heart?
Increased heart rate and bp
Sympathetic response in lungs
Bronchodication
Sympathetic response in glucose control
Glycolysis and gluconeogenesis
Sympathetic response in GI
Decrease in gut motility
Parasympathetic response in eyes
Pupil constriction
Sympathetic response in heart
Reduced heart rate
Sympathetic response in lungs
Bronchoconstriction
Sympathetic response in GI
Increase in gut motility
Sympathetic response in bladder
Micturition (action of urinating)
Bet a bookers act on what receptors
Broadly alpha + block beta adrenoceptors
When activated by catecholamines eg adrenaline , beta-adrenoceptors do what?
Stimulate ademylate cyclase
Conversion of ATP to cAMP
→ heart muscle contraction, sm relaxation, glycogenolysis
Glycogenolysis
Breakdown of glycogen into glucose
Example of non-selective beta blockers
Propranolol
Clinical uses of beta-blockers
Treatment of: hypertension
Ischaemic heart disease
Cardiac arrhythmias/ abnormal cardiac rhythm
Heart failure
Symptoms of anxiety
Role of beta-blockers in hypertension
Reduce secretion of renin
Reduce heart rate → reduces CO
Some non-selective beta blockers are also alpha1 blockers so vasodilation
Line of treatment for hypertension -> beta-blockers are what line?
Usually 4th or 5th
Role of beta-blockers in ischaemic heart disease and angina
Reduce myocardial oxygen demand
Improve conony blood flow
Antiarrythmic effects
Also reduces renin- angiotensin - aldosterone axis activity= reduced cardiac remodelling
Lowers bp
beta-blockers for ischaemic heart disease and angina co-prescribed with?
Anti-platelets, statins and ACE inhibitors
- bb one of two first line options in treating angina symptoms
Cardiac remoddelling means?
Heart ends to get a bit stiffer and is less able to pump, therefore beneficial to reduce it
Beta-blockers co-prescribed with?
ACE inhibitors and aldosterone antagonists
Role of beta-blockers in heart failure
Similar mechanism of action as impact on ischaemic heart disease
Particularly antiarrhythmicand reduced cardiac remodelling
Role of beta-blockers in arrhythmias
Slows down heart rate
Beta blockers can reduce chances of -> In some cardiac disease, the ventricles start the electric signal ( depolarisation) , which can be dangerous → ventricular tachycardia or ventricular fibrillation
Adverse effects of beta blockers
Lower heart rate and bp
Tiredness, fatigue, dizziness
Sleep disorders and nightmares
Erectile dysfunction
Peripheral coldness and (raynauds phenomena)
